i don't consider myself a Clyde - i'm a smidge over 6 ft, and fluctuate between 200- 215 lbs. but pressed to guess my weight, most folks think i'm around 180-190. have no idea what my % body fat is, sorry. but that's up from my low of 120 in college.
i ride an essentially stock '05 Bianchi Eros. haven't broke nothing yet.
i also ride a '91 Trek 930 SingleTrack. i've broken lots of stuff on this over the years, but nothing i'd consider extreme.
to the OP (Motophoto): i love the Klein - seriously old-school saddle! plus, i can't remember when i last saw a frame with bottle mounts below the down tube. what year is it?
oh, btw, cross-chaining is often considerd a bad thing.