- the compromised position (american position) is beneficial, if your speed exceeds about 30-35 km/h on average (Tour-Magazin 04?/2009), so your olympic distance bike split should be less than about 75 minutes
- the seat angle can be changed by installing another seat post and moving the saddle. I ride a steep angle on my road bike.
- The seat angle should be increased, otherwise the angle at your hip is too low (look at the bike fitting articles at
http://www.slowtwitch.com) Tri bikes have seat angles of 76°-80°, road bikes about 74°.
- the weight distribution is the main issue. Road bikes are not designed to be ridden in a very steep aero position with lots of weight on the front wheel. It will change the handling characteristics of the bike dramatically, not necessarily for the better. (the round cut out in the rear is because they want to get the gap between wheel and frame as small as possible, for aerodynamical reasons)
- Look at e.g. the German tri league. Most riders have shorty bars on their bikes. TT bikes / pursuit bars are not allowed because of drafting being allowed. I think also in Olympia some used ITU-compatible bars (not reaching before the brake levers), but I cannot find any pictures at the moment.
- For me the main reason to put aero bars on my road bike would be that I have another position to choose from. As long as I maintain the same body angles as if I was deep in the drops I will not change the handling (too much) and I'll benefit from being able to relax my arms and shoulders a bit. Being able to ride without tiring is a huge benefit (the benefit of a closed jersey zipper is about three minutes for a 40km bike split at an average of 35 km/h, still I'd open it if it was too warm).
- I also don't have the money to buy (and room to store) a TT bike.
So I'd say: Don't try to achieve an aggressive aero position on a road bike. It cannot (and should not) be done. Go for the compromise, but keep in mind that the drag coefficient will not decrease dramatically.