I just wanted to add my experience to this discussion, maybe it will help some people.
I learned SAM from RandyG back in 2006 I think, I also spoke with Hal once and he explained what I think is the fractional system, (like the inverse of SAM). When I first learned SAM it was great, I was more confident, pocketing balls very well. Eventually though, my shotmaking diminished. Now before SAM, I was using the ghostball method (didn't even know that's what it was called until I spoke with Randy). And I pocketed balls pretty well with it.
So here's the problem I had with SAM and Hal's system. I became too confident, I knew where my aim points were but I would still miss shots, even though I swear I was hitting the aim points. What I think was happening was those sub-conscious adjustments weren't really happening anymore (I'm not really sure, just theorizing). Meaning i was becoming a little too precise, when a shot is "in between" aim points, shooting exactly at the aim point wasn't working.
I fixed the problem though, real simply, I just make myself visualize the ghostball, and then use SAM to aim while getting over the cb. This accomplishes two things. It slows me down. I walk over to the object ball, look behind it visualize the ghost ball, Walk slowly back to the cb, and line up. When I'm over the cb, looking down the stroke line, I know I'm looking at SAM points (I can't get rid of this, I learned it too early in my game and its stuck), but for some reason this process forces those "sub-conscious" adjustments again. And of course, this visualization really "cements" the shot for me. SAM is aptly named "supplementary".
Further, SAM only really creeps into my head when I'm in "practice mode". When I'm simply playing, or playing ghost etc. It completely disappears, and I'm pretty much only using ghostball/"feel".
This method seems to work for me. As far as aiming for spin, I just practice plenty of shots with spin. One thing that works for me, is setting up a straight in shot, 1 diamond distance between cb and ob, and making it with one tip of side spin left and right. then increasing the distance, still shooting the same speed. I'm not really sure what I'm doing to make these shots work, but eventually I started to develop a "feel" for it.
I've tried backhand english before, and still use it for certain shots. But I prefer this "feel" method.
