Just keep doing what you are doing. WM and PD know best. I'm surprised there isn't a WalMart near you with the HTH 6-way drop test kit. That's the best thing short of the Taylor K-2006.

WaterMom uses bleach in her pool. I use Liquid Chlorine in mine. Same thing, but there is ONE store that sells LC in 5 gallon carboys that turns it over so fast their stuff tests out at 14% though they nominally sell it as 12.5%. What's the difference between that and 8.25% chlorine bleach? Only in the amount of chlorine added to your pool.

If your pool was 10,000 gallons, one jug (121 ounces) of 8.25% bleach will add 7.8ppm of chlorine. But if you add 1 gallon of 12.5% LC, it will add 12.5ppm of chlorine. (you need twice as much of each to get the same addition of chlorine in a 20,000 gallon pool). That's the only difference between bleach and LC.

As for bleaching your liner, you need to really raise your chlorine level very high before you do that--and EVERY kind of chlorine can do it regardless of the source.
Generally, if you "shock" your pool to the recommended level based on your stabilizer (aka CYA) level, you have NO fear of bleaching your liner. However, over the years, the sun WILL fade it anyway. Personally, it's not a big concern of mine as long as it's not weakened. But that's me.