I could definitely see what you are saying about throwing rods if ur ratio ends up having you tapped in second. Very much agree with the marginal gains at that rpm as well. The 520 checks out pretty early on the rpm range. Too wide of a gap from 2-3 to gear down a bit and let it tractor in third?It was a combination of things. First off they are hacks at Thumper Racing and don't take their time to do a good job, but the other issue is on a wide ratio bike the 520 piston takes out the stock KTM rod likely because you are revving the pi$$ out of the bike in 2nd gear all the time. The CP piston is a really nice piece and was fine, both of them. I loved the BB when the bike was on its wheels because the major gains are down low with added torque, you just keep on short shifting it which is easy on the con rod. On the snow the gains aren't nearly as obvious or useable, its a bit better than stock but not worth the money or drama.
When I bought my first BB Travis was telling me he had tons of BB snow bikes out there, when it blew up it was oh well its a snow bike what did you expect, quote "I don't see how this is my problem" even after they admitted to installing the wrong crank seals. Idiots.