Two dogs,
Do not confuse me with the factory, but my comments were just an opinion in this case, and stated as such, that with a very small sump Qty, leaded fuel and high f/a ratios that more often would be prudent. In fact Rotax recommend this is using leaded fuel. As for head torque, sure they could design a better method, like a TCM/LYC design, but it is not.
RA....that is a long bow to draw as you say, but yeah I can see it is possible. I doubt the C98 or BP98 would be enough of a change in thetaPP and the timing is fixed, but what else? Again how would we know. Not enough data or evidence so far.
UL
the Rotax engine is a water-cooled head and a bit different to an air cooled TCM/LYC etc in that respect. It has a similar compression ratio or a bit higher and 26DBTDC, so it is taking advantage of the H2O and 98PULP