playing tight(ish) at the early stages of a tourney is ok, or you can try to accumilate chips by being a selective bully. Because the stacks are deep(ish) at this stage, you can treat it as a cash game if you want, and both strategies can work.
However, when you get to the middle/late stages of a tourney, and the blinds to stack ratio is high, plus some tourneys have antes at these stages, then stealing becomes a must. You cannot hope to have enough strong starting hands to play, otherwise you'd simply bleed to death. Harrison talks of the concept of 'M'. Put simply, 'M' is the number of rounds you can play before you go broke. Its silimar to working out how many BBs you have in your stack, but adds a little more precision. For example, if blinds are 1000/2000, with an ante of 100, then it will cost you 4000 per round (on a full table). If you have 20000 in your stack, then you have an M of 5.
In order to steal effectively, you must have enough chips to threaten anyone who calls without a strong hand for maximum FE. An m of 5 is normally considered the minimum you should have in your stack, and you should be trying to steal way before this point.
The best way to steal is to push allin when first in, that way, you gain maximum FE. The flip side is that you would normally only get this chance when in EP, and you run the bigger risk running into strong hands. You should not try to steal with total trash, but even one gappers are ok if you are first in, as unless you are called by an overpair, you still have a good chance as you are unlikely to be dominated. You should also push your aces the same way as you do 78 suited.
Lastly, NEVER call standard raises at this stage, unless you have a very high pair and is hoping to trap. You should also fold all small pairs if the pot is opened (unless you are in the blinds). With Medium pairs, you need to either push al in or fold, depending the players who has already come in. The same goes for calling an allin with medium pairs; if the player pushing has been doing it almost every round, you should call, but if the player has dust on his chips, you should normally fold.
