Today I made a first recording of Tchaikovsky's In Church. It is an RCM grade 5 piece, and my level is grade 4, not grade 5. However, it went very well, because this piece is very suitable for a Molly schedule. I started ages ago, my first section was learning four RH chords. In all, I think I made 13 HS sections, patiently practising just those sections that were scheduled for the day and nothing else. Then it was time for HT and I made new sections and once again practised these with a Molly schedule. Finally, I started playing through.
I have been surprised by how smooth everything has been. Without the Molly schedules, I would have struggled so much more - because I would have tried to practise more than I could manage. Or, to be exact, I would have practised what I just could manage - and just managing means to me, making lots of mistakes.
The big take-away for me is, start a long, long time before you think a piece should be ready.