I just got a new tri bike which is a size 54 top tube at 76.5 degrees. My old (road) bike had a top tube of 54.6 but I ran a reversed Thomson post which (per Thomson) gives you 1.6cm set back (or set forward as the case may be) thus making an effective top tube of 53cm. Old bike had seat tube angle of 74 degress but I calculated the forward post put me at 76.5 degrees.

Assuming I was using a size 11cm stem before, can I just drop to a size 10cm stem on the new bike and have the same overall seat to stem demension? In other words 53 + 11 = 64 vs 54 + 10 =64. Seems to me the later is the preferred scenario since it seems more balanced. Does this seem logical? Thanks!!

Mike