You don't cap (4 bet) from the SB or BB?

[DawnToDusk]

I'm just looking through my SSHE and at the charts on page 80-83 which give some preflop play guidelines. Something from those charts caught my eye too. It seems like they don't have you capping (or 4 betting depending on where you play) in the small or big blind.

Does anyone know why this is so? Do they just assume us to use the same guidelines and didn't print it for spaces sake or is there another reason?