Originally Posted by sumgy

Given the 61cm frame has a 583mm seat tube, I would guess that the exposed post is somewhere near 30cm.
That quote from Greg Lemond is interesting, because in this case there is likely almost triple the amount of seatpost exposed vs inside the frame if using a 410mm post.

Edit
The HT is only 18cm, and there is much more than 18cm exposed seatpost IMO.