Sorry, trying some txt-spk there! To wait, or not to wait: that is the question. If someone hesitates, should the rest of the band wait so that the bells strike in the right order, or should they relentlessly follow the rhythm? On tower bells we don't have a lot of choice, because of the intrinsic rhythm of each bell's swing, but on handbells we can decide (to some extent) which mode we want to ring in.
Ideally we should try to create our own intrinsic rhythm and follow it regardless of hesitations: a mistake should cause a gap/crunch but not alter the length of the change. But when getting started on plain hunting with a learner, I think it's necessary to wait for her, so that she can see that her bells are ringing in the correct positions within the change - even if they are late and the rhythm is poor.
At what point should we stop waiting and switch to relentless rhythm? I would say that when ringing on 10 or 12, it's important to keep the rhythm up and just let bells be out of place if they go wrong. Also in our Surprise Major ringing, I think we've got much better at keeping the rhythm going despite mistakes.
However, when ringing Bob Minor with Thomas, the situation seems different. Because he still swaps his bells over quite a lot, I find that I need to concentrate hard on checking that bells are in the right places from change to change. If I want Thomas to ring in 2nd place, but he hesitates and another bell rings according to the rhythm and jumps in instead, I find it very disruptive and difficult to cope with. So in fact, I am expecting us to wait for Thomas to ring, and to make sure that the bells strike in the right order even if there are large gaps. I am now realising that it's important to explain this to the rest of the band, so that we are all ringing in the same mode.
I think I am right in saying that Abel and Mobel have a "wait for me" option, although I don't seem to be able to find it in Mabel. I have the impression, based on personal conversations, that Chris Hughes resisted including this option for a long time, because of the idea that a simulator should ring perfectly and force the ringer to fit in with it. Roger Bailey, and perhaps others, argued for including "wait for me", mainly (or at least partly) for handbell learners.