From what I read CYA is a big problem for year round pools, but I am a touch longer than memorial and Labor Day.
Some pools that pump out a bunch of water for closing and then refill again over the winter with snow melt and rain in fall/spring might be fine with pucks with regards to your CYA level, but I can almost guarantee they're not really as sanitary as you'd like because you aren't keep an eye on the FC levels. Bottom line is that it's your pool and you can manage it how you want to. The way it's done here, it takes all of the "maybe"s out of the equation and you can feel more certainty about your water.
I'm a May to Sept pool owner and the CYA still catches up to you. Might take a year or two, but when I took over my pool the CYA was ~140.
Let's say you've got a 12 week season, and you have an average daily FC consumption of 3ppm.
For every 3ppm of FC added, trichlor pucks will add 1.8ppm of CYA.
So your Summer looks like this:
Week......CYA Level
1...............12.6
2...............25.2
3...............37.8
4...............50.4
5...............63.0
6...............75.6
7...............88.2
8...............100.8
9...............113.4
10.............126.0
11.............138.6
12.............151.2
Now, each week your minimum FC level is going to increase. So you'll need to "shock" weekly to bring this up. As long as you don't use Dichlor shock, your CYA won't be impacted further by this. But now you're dumping in a bunch of liquid chlorine weekly anyway, instead of just a bit throughout the week.
Toward the end of the Summer, minimum FC levels are going to be harder to maintain, but you might skate through the Summer with no algae.
If you drain/fill 50% of your water as part of closing and re-opening, you start this cycle again next Summer -- but with a starting CYA of 75.6. By Summer 2 or 3 it's unavoidable that you're going to need to pre-emptively drain/fill or deal with an algae outbreak.
And unless you're closely checking these levels (so still testing), algae or no algae your water might not be "clean".
Anyway...
Typing all that hurt my brain. Dealing with all that sounds like a painful method of pool care. Mine, with no SWG, is:
- Test FC/pH every couple days (~5 minutes)
- Add ~32oz of liquid chlorine daily (~2 minutes)
- Run all tests weekly (~15 minutes)
I also try to run at the higher end of the FC/CYA chart. I can skip a day and double my FC addition and it's no sweat.