i am trying to wrap my head around this stuff because it remains too conceptual based on my experience. if we remove the style/era/trend component out of the equation (mine, at least...) can someone cite an example of what tube diameter substitution in place of another tube yields what difference in feel. is there a moment in a race, or a ride, when you said (for example), "that (tube type goes here ------ > _________ ) changed this (the "this" goes here ------ > _________ ). i am not talking about the frame design or whether the bicycle fit better - the question relates to the OP and the three choices. thanks atmo.