If my bike were opened up like his, that crank would be welded before it went back in, even if it were on my dime. Then I wouldn't worry about it affecting the warranty.
I would have to agree with you on this aspect, however unless you catch an understanding dealer that will do this for you, they usually will not vary from the norm with a reassembly because it leaves them liable for any problems that can be associated with the crank then. It's understandable but possibly if Mike were to approach them and give them a "release" from liability, maybe they could go this route with the crank. It all depends on the dealer and if the warranty is near an end, they may go for it.