This simply could be my bias manifesting itself, but I tend to see more TT oriented folks going with straight and the S-bend family of extensions (not exclusively though). Conversely, when I am out on training rides or driving about most of the "multi-sport" athletes I tend to see are on ski bends (of varying length). I think this is a case were vanity, tradition, and lack of a need for extended comfort is driving the TT folk's decisions. For my part I have been sold on Ski-bends, but still like how bikes look with straight or S-bend extensions (purely from an aesthetics standpoint). Also, while true S-bends strained my wrists toward the end of 40K, the F-bend style never did. So, I think it boils down to individual comfort and specific intention. Oh, and vanity. :)
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