[RandomUser]

The 21% 4th street number proves you are sticking to good solid starting hands. The tight players I see are typically 20-25% with many players in the 25-30% range (and the handful of 40% maniacs).

And yes, the 40% win at showdown is abnormally low for good starting hands. The stats I've seen typically are 55%+, especially for tighter players.

This is just variance taking its toll. If you can maintain your good starting hand selection, this will turn itself around the long run (although the long run can be 10-20K+ hands).