If you pay attention to almost ANY production metal frame, you'll find all manner of issues at the seat collar. I have yet to find one with nice smooth, rounded edges at the clamping slot and on the top edge. And no bike shop building 100's of bikes a month will flex-hone a seat tube. Most shops don't even have a flex hone on the tool board.
So anyone using a carbon seat post would behoove themselves to take a really close look at their frame's seat tube clamping area. Spend some time with small files to round the edges of the slot and its rounded bottom, the top edge of the tube, as well as flex-hone the inside of the tube. Then use quality sandpaper like silicon carbide to finish the edges. (If there are any burs, then remove them manually BEFORE flex-honing, as this process doesn't actually remove offending burs, etc., it will just "smooth" them.) If you think anyone took the time to do this on your bike, you're sorely mistaken. I've done this to most of my bikes out of habit. I just like knowing there aren't sharp metal edges digging into my seat post as I clamp it and ride, regardless of seat post material.
Last edited by LV2TNDM; 02-10-23 at 12:55 AM.