I play both tourneys and cash games and the biggest difference as you have surmised is chip stack depth.
When we are deeper, this means our decisions trees get larger and grow almost geometrically.
The majority of a tournament is played at 40bb or less
, direct odds
are going to be the dominating factor in our decision making process. We bet or raise to deny pot odds
which then means play shifts entirely to the value end of the spectrum, that is, you have to play value hands almost all the time. Once you call a raise, the SPR (Stack to Pot Ratio) is such that stacks are pretty much going in on the turn or river. ANd this is especially true when the blinds fall below 30bb...
However, in the cash game, you are almost always beyond 100bb and often 200bb+. Now we enter the realm in which IMPLIED ODDS become just as important if not even more important than Direct Odds. What this means is that plays that were not profitable at 40bb deep now become profitable. At 30bb its mathematically incorrect to call a raise or 3-bet with hands like 87s whereas at 200bb it "can" be profitable to call.
You now have room to maneuver, to plan, and to plot. On the opposite side of the spectrum, when you are really deep hands like AA, KK, TPTK, etc actually start to carry Reverse Implied Odds and can actually hurt you. So we go from having AA and being comfortable shoving flop/turn for 30bb stacks to having AA and being uncomfortable shoving flop/turn for 200bb stacks...
So how do we play deep stacked? Well, we have to employ all those poker concepts and fundamentals as well as adjust to each street.
Harrington on Cash Game Vol I has a decent section that talks about the difference between short stack and deep stack play...
anyways, this is a complicated subject, but I would state simply that the biggest difference is we go from a "Direct Odds" centered orientation of play to one in which "Implied Odds" become just as important if not more important than Direct Odds.
Players that have the most trouble adjusting to Deep Stack play usually are players that do not understand how to integrate "Implied Odds" into their playbooks.
Kinda like that saying, "When all you have is a hammer, all your problems look like nails..."
Well, in poker, I find many tourney players just can't help but to play solely based on Direct Odds when in the cash game, there is another dimension called "Implied Odds" that are just as important if not more important than Direct Odds
hope that makes sense...