Isaq pointed this out in his latest submission, and I agree that it is a bit vague.
I was originally inclined to time from gaining control of one's character. I however recognise problems within this timing method, as I have come to realise recently. The problem is that timing ends up being inaccurate because it can be hard to judge exactly where one gains control. In general, it's better to start and stop splitting where the player is largely inactive in the game (ie. sitting through a loading screen, shortly after pressing a menu option, spamming through a text prompt, cutscene etc.), to eliminate timing inaccuracies.
The option that I can see as being feasible is timing from pressing "restart". This would make timing a lot easier and simpler. I would be willing to retime existing runs, which wouldn't take long at all, to meet this convention.
For ending, I recognise that fade out is also hard to split at, so maybe splitting upon pressing A? Which can be visually confirmed by the Rabbids starting to pick up the item.
What does everyone think?
I do agree that gain of control can be hard to time (I have some experience with that... two runs were retimed) so from reset would be easier. But I don't think that pressing "a" to pick up the XL-stuff is good as an end point, especially not for the levels that do not have an a-press prompt at the end.
Oh yes, I forgot about that. Shall we keep the rule for ending on fade out? If so, I'll retime the runs now.