Hope you wont really want me to count the number XD
i like to ;) Cause i don't see the trend.
My B3 rounds: 2 times SG, 4* SF, 1* C(who performs real bad) as SF starter
In my roster the order is SG, SF and then PF while you could discuss if the PF is not the best but he is even better as a PF and needed there most.
U21 WC last 6 games, i count all who played most times at SF(above 5min):
PG: 4
SG: 12
SF: 2
PF: 2
C: 4
NT last three games(4 teams):
PG III
SG I
SF IIIII
PF III
this also result into the training time, which make it hard for them to be effective at U21 level. and the bad recognisation in SF of the system. My SG is for me clearly an SF, he lacks a bit in IS but this isn't even part of his salary afaik.