I'm pretty new here so I'll leave everything else to the awesome TFP experts, but one thing I CAN say is to make sure you check the age of that Home Depot chlorine (printed on the box). At my local HD they store it outside in the Texas heat, and some of the boxes are MUCH older than others. And the boxes that look the worst aren't always the oldest either!
The last couple of boxes I bought were from a Home Depot location that had been out of stock when I bought my first couple of boxes. So I'm sure this batch they have should be reasonably fresh. Those boxes aren't quite up to the task, though, so it isn't unusual at all to see a bunch of loose jugs. And they don't have bar codes on them, which tends to annoy the clerks at the check out stations. Oh well.
Well, it's been several days since I've posted a comment here. Haven't really needed to. I've settled into a routine now of testing the pool water every morning after I've made my first cup of coffee. I just have a seat in the backyard with my trusty TF-100 kit and test the FCs and CCs every morning, then do a complete test every week. This has been working well. I'm having to add chlorine almost every morning -- the amount varies -- but I guess this is normal. The main thing, though, is the pool's water remains crystal clear. Last week I had to SLAM for a couple of days, but it passed the OCLT so things have settled back to normalcy. I've found that, as long as I maintain this simple daily routine, the amount of time I'm actually having to spend on pool maintenance is now minimal.
I've done a rough calculation on consumables -- chlorine, in this case -- and it looks like I'm averaging one of the Home Depot 3-packs every six days (not including SLAMming of course, which would increase costs, obviously). So that's five of the 3-packs per month, or $50 per month. Sure beats paying that incompetent pool guy $150 a month to screw up my pool. By a long shot.