It's probably worth noting that a lot of pros ride what look like pretty small frames, with great success. World champion Peter Sagan is 6 feet tall also, and his frame can't be much bigger than 54-55 cm. You can't argue with the success he's had.



There are advantages of having a smaller frame underneath you, I think it's referred to as "flick-ability". Good for climbing and sprinting, where you are throwing the bike around a lot. Lighter too, but that's not the main reason.

There's no trick to making a too-small frame fit, just get longer stems and seat posts. I like my frames on the larger side of the range I can ride, but there are lots of advantage of going small, and no reason someone that wants to can't make it work for them.