Seems like for the first one all were intermingled, maybe. Then for the second there were classes for composite, selfbow, etc. but I don't recall they, the second batch, were ever judged. But yes, generally the purpose was to assess all variations. Given the criteria, as in real life, every design/materials choice has an offsetting trade-off.
Timo is so humble, he didn't recall being the bowyer who won.
I learned a bunch about bowyerin' doing challenge bows. Mostly that a simple design well executed will pretty much hold it's own with all comers.