AM I TOO TIGHT?

[hbgolfpro]

In HPFAP, Sklansky on page 27 writes "you can play all hands in groups 1-5 when the game is typical or TOUGH". Now that being said, group 5 hands include Q9s, T8s, 76s, 97s, and even 65s. I realize that different situations call for different actions, but being that David described the game as typical or TOUGH, I can honestly say that I do not ever come into a pot in middle position...ie 4 seats to the left of the BB...with 97s, 76s, 65s etc. I play 15-30 or 20-40 live everyday and I would not enter the pot with 97s or 65s sitting in middle position with one or two limpers in front of me. And remember, David plainly states this is acceptable even when the game is TOUGH. He did not refer to the game as having to be a berry patch for this to hold true. So I ask am I playing too tightly? Am I missing out on winnning opportunities?