I need honest feedback from anyone who has attended one of these 3 day courses. Is this course for intermediate or advanced players?
I think it really depends on what you are looking for. I took the intensive a number of years ago (4 or 5 I guess), and I really don't know if the program has changed since then. Tom's information on fundamentals is good, but if your are an advanced player, then rebuilding your stroke may not be what you are looking for. That information would be more beneficial for the beginner or low intermediate player. The information on cue ball control is nothing that you can't get from other cheaper sources, in my opinion. The final day, if I remember correctly, is dedicated to aiming systems. I personally do not take these seriously, and have not used them. If you are curious about them, or have reason to put more stock in them than I do, then you may find it worthwhile. The aiming systems are Hal Houle derived, but I don't know how the details of the systems as Tom presents them compare to those offered by other instructors teaching aiming systems.
Again, I don't know if the program has changed, but there was really no information on pattern play when I took it, and I think that for a more advanced player, this is really crucial. Personally, I do not think that I would take it again if I could turn back the clock; I just don't really think I learned anything new. But I had read a lot of books by that point, and there are certainly players who will learn things, and maybe even things that are really important for their game; I just wasn't one of those people. If I had the money back, I would invest it in private lessons with a good pro to work on decision making, patterns, etc.
One last point: however small the class size may be, it is still a class, meaning that your own particular level of skill is not going to dictate the pace of the class. I find that a bit frustrating, which is another reason why I would choose individual instruction. Some people do well in a class setting; the question you have to ask is whether you are such a person.
I hope this helps!