i'll get flamed for this, but "compact frame" is the term
given to all stepchildren of Giant bicycle's early 90s attempt
at a three-sizes-fits-most mentality. in the beginning, it
was thought to be more efficient to produce fewer sizes
and have available more seatpost/saddle assemblies,
etcetera to tweak the three (or so...) sizes into possibly
fitting more folks. my opinion is that if they did not have
the alliance with the ONCE team in spain, few would have
paid attention back then.it's amazing that it became such
an aesthetic - newer riders look at these types and are used
to it - to the point that they cannot stomach a level top tube
frame. despite the shorter seat tube and the longer seat post,
i still think it as a copy-cat design, not unlike the straight
blade forks which were a colnago original attempt to dial
out some of the problems inherent in matching curves in
tens of thousands of forks. there's a saying i always remember
when the discussion returns to issues like compact frames
and other cost savings production methods:

"capitalism has a way of absorbing the marginal into the mainstream."

i don't know who it's attributed to or where i read it, but it
resonates with me.