Good point about Head's Up play. I did not realize in HU, it's basically 50\50 for either guy to win, assuming neither has pocket pair. I want to learn more about this. What other major differences and rules of thumb are there for HU play, as compared to playing at a table with 5-8 guys?
Well, HU is super-complex compared to other styles of play, because you will be playing far more marginal situations. It's more profitable if you're good at playing marginal situations, but it's more something for advanced players than beginners.
I wouldn't say you're 50/50 to win without a PP, because it's just so likely that no one will land a pair and it'll end up as a high-card battle, so very often high card broadways (Kings and Aces especially) are good showdown value hands and it's correct for you to just check/call them down to get value from Villain's bluffs. For the same reason, you
are automatically ahead most of the time with any pair, but if the board dominates you (and especially if the board hits Villain's value range) you should proceed with extreme caution. In general, 1) most situations you'll be in are marginal/difficult so you'll have to have a good read on the situation, and 2) value ranges are usually worse than they are in multi-handed play (you will however, often get into tight dynamics where both of you play a lot of hands but have a tight value-betting/calling range so you'll be checking down a shit ton of hands, particularly against experienced players).
It is tough and takes a lot of practice to learn HU, but it's definitely worth your while. It teaches you faster than anything else how to navigate and exploit marginal situations (which helps your game in all formats), and it's vastly more exploitable than any other format.
I strongly advise against multitabling HU. You need to adjust and read a ton to play HU (plus you'll be playing every other hand at least and few of your decisions will be automatic). If you must multi, no more than 3 tables at once. Any more and unless you're a multitasking wizard (if you have a penis you're not, trust me biology says so
) you will not profit.