Rossin Columbus SLX f+f, or not..?

Doesn't quite work like this in practice. There are no flutes/grooves/rifles in the seat end of the seatpost (think about it), nor in the BB shell. AFAIK on SLX they are in the bottom bracket end of the seat tube and chainstays and on both ends of the down tube. Not easy to get a finger in these places to check.

I didnt say seat post I said where the seat tube meets the bracket shell,its quite easy to check without the bottom bracket installed.