I've been ringing for over 50 years and I have even rung peals of surprise major, not that I ring many peals. I have a quite limited repertoire of surprise minor methods: most towers around me are lucky to get beyond plain bob (with a few exceptions). Thus, a quarter of London has been a target of mine for many years.
I achieved this target yesterday but had to drive 20 miles to do so. It was a branch quater peal day. Whilst it went very well, we had 2 false starts of a couple of leads each. It was not me who went wrong but, as the 'least experienced' surprise minor ringer, it was suggested that I might like to glance at 'the line': I didn't need to. Once the person who did go wrong had woken up the ringing was a lot better.
As it turned out, after we had rung up, I toyed with putting a knot in the rope so that it would be shorter but it was on the cusp of needing one. After false start 2 I did put a knot in and, by the end, I was glad I had.
It was rather embarrasing for the conductor at the end for him to be told by a clearly very experienced ringer that he had used a false calling for the 720. He had called W, H, W (twice repeated) from the 6th. However, on checking, this is in my Ringers' Diary (2004) so I do not understand the problem.