I'm still preparing! I have collected the following questions:
1. Should I do a deep clean on the sand filter before the slam?
I would do a deep clean, wont hurt Either way, should I do one after the SLAM has completed and all tests passed?
yes you can, no issues
2. When, if at all, should I use recirculate as opposed to filter during the slam?
That is a good one, most people use it when they just do not want to filter, most of the time I have heard of the DE filters getting clogged and the pressure rising faster than 8 hours while they are at work.. with that said, if your filter pressure is rising more than 25% from clean pressure in 8 hours/while your at work then use recirculate. I do not have a due date on a clean pool, I have POP, but I was wondering about the changing PH chemistry from hose water and loss of cya during all those backwashes impacting the efficiency of my bleach adds.
you will bring your water to correct levels before you start the SLAM, once you start the SLAM dont worry about PH or CYA..
3. Found
"Hayward W530 Large Capacity Leaf Canister with Mesh Bag Replacement" online and wondered if it could be used between the vac head hose and the skimmer basket hose in. It is several times bigger than my skimmer basket! I might be able to do that instead of siphon or trash pump if you think it would work as I imagine it, or however you suggest. I just bought one, mine is here and it works great, everything gets collected before it hits the pump
4. Leaf debris in pool is ridiculous here. What's my best option to keep the leaves from clogging the skimmer basket? Currently I am afraid to leave it on when no one is home or while we sleep. I am imagining plastic 2x4 attached to the leaf rake basket all mounted to the side railing a few feet before the skimmer basket.
for leaves or anything else in the pool I use "the pool cleaner
attached to the above zodiac.. with both of those cleaning every time the pump comes on my pool is leafless and spotless
5. Must all sand backwash last 3-5 minutes during the slam or just the 20-40 until clean? Also, 20 second rinse good for either duration backwash?
untill it is clean, may be 30 seconds and it may take 5 minutes, just depends on how much gunk its filtering
6. I was wondering how fast the chlorine sanitizes and oxidizes the nasty stuff. If I borrowed a boat trolling motor,circulator pump, or even used a trash/sub/sump pump to move it around within the pool itself during slamming, would that reduce the time I would have to wait between retests?
just use the pool pump and filter, that is what it is designed for, brushing the pool is better for it and you get free exercise 
7. What is the upper limit of calcium in a vinyl pool? I'm wondering because I am sure there will be times I'll need to just throw some on hand calhypo in when I'm out of bleach and going to the store isn't tempting. (in the future, not during the slam)
we do not recommend just throwing anything in, we test and add specific amounts for what is needed.
8. In planning for TFP yearly costs, using 2.5ppm/day, I'm coming up with 63oz of 8.25% per day; so basically one 121 oz jug every other day, totaling 180 jugs/year @ $3 each, for a yearly bleach total of $540. Obviously there are the occasional water, MA, baking soda, and CYA, but right now I'm mainly focused on the big one, bleach. Is that about right?
I think your price may be a little high but it really just depends.. I went to a salt water generator for that exact reason, all chlorine comes out to just about the same cost, SWG is upfront cost and bleach/chlorine is lower but you will always be going to the store to get more.
Thanks!