Ok, time for me to get busy. I've played two short sessions this week following the first lesson and spent many hours thinking about the skillset and learning process (that I should have been playing) and I have a number of comments.

It feels to me that the first lesson pre-supposes that the learner knows the game and the rules and plays recreationally and for fun, but loses slowly over time because he's playing too loose and ending up in spots that he does not have the skill to play profitably. The first lesson seems to be a band-aid that seeks to slow the bleeding of chips through the TAGG cure-all - to ensure that you at least start any hand you play with better equity on average than the opponents.

The first lesson to me looks like it's trying to plug a leak by preaching discipline in your selection of playable hands. I mention it in this way because I think that while teaching a play style is likely to make the learner profitable it doesn't really teach the learner much in the way of fundamental poker skills (except discipline). In my head I'm building a list of what I consider poker skills and I would ideally like to have every lesson focused on learning or practicing one or more of those skills and to me the first lesson doesn't really teach anything beyond discipline. It could be argued (and possibly rightly so) that the purpose of the first lesson is to mold the player into playing and thinking in a specific way that is a requirement for the following lessons to be appropriate and beneficial, but I'm still not convinced by it.

The first lesson has a post-flop section which outlines very well the 'post-flop is hard' observation while trying to make it easier. It succeeds in part, as it provides a way to think about and act on the flop, but when it comes to turn and river play it suggests that you should have a plan but doesn't seem to me to provide that much guidance. To provide generic guidance for all post-flop play it might be an idea to discuss how much of your stack is justifiably put in for a given strength of hand.

For a beginner post-flop section I would consider something like the following simpler to follow:
Understand how pot sized bets (heads-up) mean that the pot is 3 times bigger on the turn and 9 timers bigger on the river than it is on the flop and consider what that means for all betting decisions.
Try to play a pot that by the showdown contains:
Straight flush, quads, full house, straight, flush, sets: All of your stack
2 pair: Half your stack
1 pair: Between one fifth and one quarter of your stack.
High card (like A or K): A tenth of your stack
Every time you are faced with a decision (check/call/bet/raise/fold) consider if you are ahead or behind. If you think you are behind check or fold. If you think you are ahead call, bet or raise with a plan to put in as much of your stack at showdown as described above considering the strength of your hand - unless too much of your stack is already in, in which case you have to fold (and you'd have to be very sure of your opponent bluffing to do otherwise). If you are in doubt and cannot tell if you are ahead or behind: Fold every time.
In the above remember the following:
The river is very likely to see both bets and bluffs - if the pot is perfectly sized for the strength of your hand before the river it is likely to become too big for the strength of your hand on the river. This can mean that you should delay one of the bets you intend to make to the river and if the opponent is likely to bluff you have to sometimes call a bet that makes the pot bigger than you would wish it to be for your hand.
All bets must be relative to the current pot size if you want to price out drawing hands (and you usually do).

The idea I have with the above is to create a relatively simple guidance for all post-flop play that is not completely wrong-headed (it is simplistsic and in many cases wrong of course), and which can serve as a framework on top of which you can learn the more advanced post-flop plays. It can be used to describe how to lay and take implied odds and board reading ties in with that model of post-flop play well also. An assignment for a beginner could be to do some calculations for each type of hand and determine what bet sizes on which street ends up with a pot that is correctly sized.

There are a couple of important poker skills which I think it's never too early to begin learning - and which I think should be a key part of the some of the very first lessons. In some areas we can get help by poker software (sometimes the site software itself), but I think it's important to develop these skills so they are automatic regardless. I am thinking about the following:

Memorise actions: Later in the hand when you need to decide if someone has just bluffed you or bet for value you need to know what he has done earlier in the hand. Only his actions earlier in the hand will give you an idea if he is likely to be bluffing or holding a monster. This skill is a necessary pre-requisite for all at-the-table hand reading (as opposed to HH analysis with range considerations). You need to have memorised both the type of action taken at any decision point for each of your villains, as well as the sizes of bets relative to the pot made at each decision point as well as any tells (online means mainly timing tells) that give you additional information.

Board reading: The basic level of board reading is to constantly monitor the cards on the board and know what is the nuts, second nuts, third nuts etc and exactly which cards make up the nuts etc - so a half-second glance at pocket cards (at showdown or similar) will tell you automatically what the absolute hand strength of the opponent is. You should never be surprised by any straight or any flush or other made hand - you should always know exactly which hands it is possible to make and which pocket card combinations make those hands. This skill is a necessary prerequisite to learning how to categorize boards as dry, wet, connected, good for bluffing etc etc. It is also a necessary skill to ward of tilt. Tilt is often triggered by losing to hands that you did not anticipate as being possible. If you have a solid understanding what is possible to occur then even the unlikely hands are less likely to tilt you - because at least they won't catch you by surprise.

This all said, I'll skip the rest of lesson 1 and start wrapping my head around lesson 2.