Originally Posted by zymphad

Again, where are you getting that 6800 derailleurs are compatible with 5700 shifters? I just don't see it. The pull and indexing are not the same. The shape and design of 5700 and 6800 are not the same for both RD and FD. Where the cables are attached aren't the same either.

I just don't see how you can upgrade piece by piece. If you upgrade RD and STi, you'll need to upgrade the cassette, chain, crank, wheel (11 spd compatibility), FD, etc.

Just curious where are you getting info you can upgrade piece by piece and where it says the Shimano 10 and 11 spd are interchangeable. I'd like to see a thread with multiple people verifying this is possible.