frame geometry question concerning down tube angle
When a frame is fillet or tig'd, how is the down tube angle determined?
With lugs, the angle is pretty much set based on the bottom bracket and head tube lug sockets needing to line up. Straight forward.
Since that constraint doesnt apply to fillet or tig, what determines the angle? Along this line of question- is there a downside to having 1 or 2" of head tube below the down tube joint? Wasnt sure if that increases lateral flex or something negative like that.
**I am referring to a typical drop bar frame where there are no issue to work around for individual rider fit.