Sand Paper on glass sharpening, aka Scary Sharp

This is a good video: http://www.woodsmith.com/issues/165/videos/sandpaper-sharpening/

(YouTube 'scary sharp' and 'sand paper sharpening', brought up a lot of nonsense. I could only find one relevant video. The rest were about stones, belt sanders, a mouse pad! (which wasn't too bad a method)
http://www.youtube.com/watch?v=4--HIDogrc8
Sharpens a kitchen knife, 3m films, granite block, good techniques well demonstrated.

Fine Woodworking Magazine--takes a long time to get to the sandpaper method. Scroll down. This is the article that turned me on to it.
http://www.finewoodworking.com/pages/w00003.asp
(There was another article a few years back in FWW mag that compared the different methods. I know I'll remember this wrong (again) but scary sharp was better than all the machines, and the top sharpness was achieved in the end with a leather strop. Curious how memory works. I remember posting this years ago, being corrected, but forgetting what I'd gotten wrong. I'm pretty sure the machine sharpeners came up short.)

This is one of the best articles: http://dans-woodshop.blogspot.com/2009/01/sharpening-with-scary-sharp.html
But it isn't clear about direction of movement.

I've found if I make any movement in the cutting direction I'll tear sand paper or gouge my stone. Clearly I'm missing something. So I always pull, don't use an angle guide, always flatten the back with each grit change. Works for me, but could be improved on.

I think one problem may be using spray adhesive and adhesive backed sandpaper--works but may be a little bumpy. I've also found that adhesive backed sandpaper is better than using Spray 77... the YouTube videoista uses 3m film and water to stick the film to his granite block. This looks like a better method for getting a really flat grinding surface. I can see doing this for grits above 1000 after I've used the sandpaper. My goal is not the absolute perfect solution, but the best practical one I can tune up a chisel or plane chisel every couple of hours.

http://www.woodbutcher.net/scary.shtml This is the closest to the original Scary Sharp article that got the method beyond word-of-mouth.

My grits are 120, 150, 180, 220, 320, 400, 600, 800, 1000, 2000. The best source of tempered plate glass is old(70s) furniture cabinet doors (stereo cabinets) the glass is thick, tempered and the edges are not sharp. They're free, drive around on trash day, look in the basement, compliment your buddy on his stereo components, offer to remove those ugly doors. Glass can be tinted, you can use both sides if you want. I almost never change paper. A glass shop might have 1/4" tempered pieces that weren't picked up, or were the wrong size, it's either a couple of bucks from you or the dumpster.
My results with my admitted limitations are probably about 90 percent. I notice a definite improvement after planing soft cedar for a couple of hours if I touch-up the edge with the higher grits. My results are an improvement on chisels and planes brand new from the store--which is an endorsement. From poking around these videos and articles I want to change my sandpaper, get finer grits or the 3M film, pull out the angle-guide-roller (try it again), get some 1 micron (12000 grit) solution.

And if you're still reading, this guy almost convinces me to spend a $1000 on stones. Garret Hack shares a lot of really good relevant information that will improve any technique. He demonstrates how to move a chisel on a grinding stone (which should work with sandpaper on glass)
http://www.finewoodworking.com/SkillsAndTechniques/SkillsAndTechniquesArticle.aspx?id=28819