Originally Posted by
fietsbob
.. as long as you can find a long enough seat post... that wont bend under your weight.
Considering how mtb's are subject to way more stress and have been showing tons of post for years, I can't imagine this being a likely problem. The stock 350mm post on my Casseroll fits with plenty of room leftover, I think most sloping tt bikes ship with at least 300mm posts, and even then 400mm is not hard to find.