Babak,
Glad to hear Landmark has been such a help to you, truly.
My point is, that it's using Buddhist principles, marketing and making money off them. Is that a big deal, not really, I suppose, let's just not pretend that some one isn't making a LOT of money from it, maybe even a few are, but it sure ain't the Buddhists or you. So they get a free sales rep, how nice for them.
Landmark is just another "way in which", which gives a supporting belief and another option to address and frame the life we are living and trying to understand -- because we want our lives to matter, ie: have meaning, as you say we are meaning making machines.
I agree, our past can not only inform the moment; it can determine and take it over entirely (there's a difference between inform and take over), such that we keep making the same choices over again depending on what meaning we give it. But meaning is not all bad, nor do I think it's to be avoided, in Buddhism this idea would be expanded, to paraphrase (or is that parapostulate) to say the meaning is in the moment, and the next moment will have another meaning.
These ideas show if we can take a moment to be where we are (be it good, bad, indifferent, etc...) and just be there, then a whole space of being opens up to us, and in this space we can make choices our habitual and learned responses would otherwise not allow us to see.
We all give meaning or derive meaning in life, I wouldn't call this pretense of thought, except of course when it is.
You would not be so attached to and in defense of Landmark if it didn't mean something to you. The ideas it has exposed you to, also mean something to you. In fact you've told several of your friends and family and the forum here just how much Landmark means to you...
Each moment is meaningful, as it informs, enlightens, and frees us.
There are all kinds of good books on these subjects, but often we like to do this kind of work in community -- that's how religions get going. I know, you'll say it's not a religion. Still the only time I've been pressed that hard to join, was when the bible thumpers have come to my door.