I've seen some videos where they just lay it down with the bitumen still on (the bottom) so that's what we'll do I think. My goodness, I've been looking at laying parquet floor videos all evening and it looks far from easy!
I wondered if you would have any luck using a sacrificial sliding mitre saw blade and a some kind of jig with that sort of thing, just to trim a very thin slice of wood from the bottom of each block along with the bitumen. Might make for less sanding in the long run?
How do u intend to remove bitumen? I have heard it can a messy job involving heat gun and scraper. @7ven