You are right, nothing is certain. This has to do with Probabilities. Anecdotal reports establish that something has the potential to cause louder T. If you do that activity, you are increasing the chance that your T will get louder. If you learn from the anecdotal report [by the way, we are not talking about one person making a post on this forum sometime over the past 10 years, we are talking about the same patterns being reported on a weekly (and sometimes on a daily) basis] you could abstain from the activity, reducing the probability of giving debilitating T to yourself.
I agree that the vast majority of spikes end up being temporary. However, those spikes can't be promoting healing. It is likely that they are interfering with healing. It seems to me that the spikes for a person with T are analogous to pain for a person with a broken arm. Both are signals from the body. If someone breaks an arm and feels pain after doing an activity that used to be ok for them, they will likely stop. The pain will eventually subside. However, if you keep doing something that results in your broken arm hurting, Eventually you will likely end up totally messing up your arm.
If you keep giving yourself temporary spikes, it is possible that eventually you might end up with a permanent spike. In other words it is possible that, either every time you get a spike, there is a small chance that the spike is permanent, so the probability that at least one of X spikes is permanent grows with X. Or every time you get a spike, the probability that it will be permanent is higher.
I can't disagree with anything you have written . Particularly as you have clarified that you are not taking into account any isolated instances. I think that the advice you give people (myself included) has always been very measured, and your message - that we can recover somewhat if we 'rest' our ears and let them heal - is absolutely right.
The problem with anecdotal evidence for me is that because of the anxiety caused by this condition, a person often loses all objectivity and the ability to recognise correlation from causation. And if one person believes that they have experienced a spike caused by an everyday occurrence (a motorbike passing, for instance) then that will lead others to question whether the same thing may have caused their spike as well. And then it looks like everyone is experiencing a spike from passing motorbikes. Even worse, people become so anxious about passing motorbikes that when one does pass them, their anxiety actually causes a spike.
I'm all for protection around loud noises, but just don't want people to develop a fear of everyday noises, because I think that can be counter-intuitive and there is simply no way of avoiding them.