Manners and Etiquette in the Tower
This is admittedly a very personal definition, but to my mind the essential difference between manners and etiquette, in all aspects of personal interaction, is that manners are based on common sense, practical effect and consideration for others while etiquette is more along the lines of rules set out by the more socially active and often more opinionated, and in many if not most cases such rules are geared more toward demonstrating superior knowledge by some and putting/keeping others "in their place" than encouraging courtesy towards others and productive behavior.
So I guess your personal objectives are likely to condition any response to my own thoughts on this general subject, which are that manners are generally productive towards the good of the general ringing community and that etiquette may have a place but not one where I want to spend any significant amount of time.
There are just two regions of activity, within the context of ringing, where I have particular views on these matters:
1. general ringing for practices and services, and "Event ringing" such as peals, quarter peals and any other specific events for which a specific band is assembled.
2. teaching of new ringers.
General Ringing and Event Ringing
Prior to any ringing taking place, someone must be designated as being in charge of the piece to be rung, whether it is simply rounds for a few minutes or anything up to multi-spliced Surprise for a peal.
The designated person in charge will be referred to here as the conductor, even if the piece is just rounds, as the conductor will need to (or at least should) listen to and assess the ringing quality and to provide corrective instruction to any ringers who are not striking their bell correctly.
Whatever the piece, etiquette has it that only the conductor should speak under pretty much any circumstances, a couple of notable exceptions being -
v If there is any risk of physical harm coming to any ringers or even to bells and fittings, and in cases when a more experienced ringer feels able to respond to the situation more effectively and/or more quickly than a less experienced or less able conductor.
v If a less experienced conductor clearly has little or no appreciation of whom or how many other ringers have gone wrong, and has not taken the necessary decision and called for a return to rounds or to stand.
Some would hold that the etiquette should hold even for the second exception offered above, but bearing in mind that poor or even unrecognizable ringing is not only a waste of time for the conductor but for the whole band, after some reasonable amount for time to allow the conductor to make a decision on how to correct the situation or to terminate the ringing, I would not be among them.
A less extreme case would be where one ringer has gone wrong and failed to correct his- or her-self, but it is clearly a distraction for the other ringers to have to crash through the errant ringer to ring their own blue line.
The majority of conductors I have come across are not averse to other able ringers, whom they know and know to have adequate experience to correct quickly and effectively, to say something if he or she (the other ringer) notices the errant ringer more quickly than the conductor, the latter having to keep his or her mind on the composition and coursing orders as well, but also expect a reasonable amount of time (perhaps a whole pull or two) be waited prior to comment by the "other ringer" to allow the conductor the chance to respond to the errant ringer, as the conductor is also (one hopes) trying to keep track of all the other ringers and cannot therefore be expected to pick out an individual as quickly as someone who just happens to be "working" with the errant ringer when he or she gets lost.
But this is getting into dealing with details that are very difficult to define.
What is clear and easy to define, is that if anything is said by anyone other than the conductor, it should be as brief and to the point as possible, and should not be said close to a lead end or other recognized calling position when the conductor may need to put in a bob, single or other call, or may want to verbally enunciate the coursing order so that other participants can make use of it.
Sometimes a treble ringer will ask if it would be helpful, in the event of the ringing becoming "a bit choppy", to call out lead ends, half leads, or when the treble is dodging onto or away from the front and/or the back.
This can be quite helpful at times but it must be remembers that one person's notion of "a bit choppy" may be very different from another's, and while some may find it helpful to know the treble's position, only one person can effectively speak at a time during ringing, and if a treble ringer is giving a blow by blow account of their activity, it effectively prohibits the conductor from saying anything without first "shouting down" the treble ringer, and that is not a practical proposition in most situations.
Teaching of New Ringers
It is normal practice (at least within my experience) for the person who first instructs and oversees a learner to continue to perform those functions for that learner whenever possible.
This is beneficial as the instructor and learner develop a specific knowledge of how each expresses any subject matter and how each responds, and if and how a response to any comment is likely to be given.
Obviously if the instructor is absent on any occasion it is helpful for another able ringer to offer instruction and if necessary correction to the learner, but an experienced teacher will have a better knowledge of how to effectively instruct the learner, based essentially on the early teaching/learning experience, and will formulate a series of steps to progress through, based on apparent difficulties the learner may have with different aspects of ringing and what aspects come relatively easily to the learner.
Unnecessary distraction from and/or disruption of those steps as planned by the primary instructor, as often (and usually) happens when others feel they have a better knowledge of what the learner needs to be told and when, can be both confusing and even potentially disorienting to the learner.
Consequently in my view it is good to avoid such distractions, and although it can require a great amount of self control not to comment when you feel something unhelpful or even incorrect is being conveyed to the learner, it is better to discuss the matter with the primary instructor and make your views known to him or her first, rather than to leap into the fray "feet first" and start directly to instruct the learner.
If and when a ringer other than the primary instructor feels that the learner may benefit from additional instruction or comments beyond what the primary instructor considers appropriate, then the polite, and I would argue correct, way to approach the issue is to ask the primary instructor if he or she has any objections to comments and opinions being expressed/offered for the learner to consider.
I have never known a primary instructor to object in such cases, although it has on occasion been apparent that they have their own schedule or series of steps planned out and are not terribly happy with it being disrupted, essentially just because someone else has few or no "ringing manners" and basically just feels like hearing the sound of their own voice.
Also, even if the primary instructor should have any objection to other input into the learner's progress, he or she has the opportunity to express these objections, rather than being left out of the interaction. This is not a productive circumstance unless the primary instructor is either dangerous or incompetent, and if that is the case he or she should not have been allowed to instruct in the first place.
I'll leave it to readers to formulate their own views on where the division between manners and etiquette falls in this instance, if indeed there is a division between them.
An Additional Perspective
I have recently (recent to April 2015) been made aware of a ringing group where, if I understand correctly, any available instructor instructs any learner any time that instruction is required.
This may work fine for their group where mutual respect between the instructors is widespread, and it certainly exposes the learner to a range of potentially different perspectives and opinions of various aspects of ringing.
There is considerable overlap between things which (by my, admittedly idiosyncratic, definition) fall into the categories of manners and etiquette, but in general they are almost all founded on reasonable and generally positive and productive premises, and are hence worthy of consideration, acknowledgement and in large part acceptance and observation.
Beyond that, as with so many things, "you pays you money and you takes your choice".