Hi Wes,
I'm sure the exact figures are in this forum somewhere, but on my 10k imp gallon pool one 200 g trichlor tab lifts the chlorine level by approx 3.5 ppm. Your pool is around twice the size of mine (ours!) so one tab for you equals 1.75 ppm chlorine. CYA is 0.6 of the chlorine dose, so you would add a gnat's elbow above 1 ppm cya per tab. Bear in mind that this is over one week, or the time it takes for the tab to dissolve.
I don't know about your daily chlorine use, but if you were to add 2 ppm cya per day using tabs, you would be using 14 tabs a week. This seems rather excessive to me.
For over twenty years we managed our pool using ignorance, trichlor tabs and a small phenol red/dbd1 tab tester. The process was the same, open pool, pool goes green, fight green by guesswork, pool amazingly clears, add one tab a week until pool close time. The water was never drained, apart from rare vacuuming and occasional backwashing, for all those years until we had a new liner in 2008. I didn't know what cya was, let alone how to measure it. Yet the pool remained sparkly clear (after the green fight) at 2-3 ppm free chlorine and what must have been sky-high cya. Trichlor tabs seem to be held in worse esteem than garlic to a vampire, yet I think that they are a quite acceptable proposition in a managed pool. After getting a better test kit I have reduced my cya to 35 (ish), and I am using cheap weak bleach at the moment, but I would have no qualms about using, or even reverting, to trichlor tabs in the future. Certainly that's what will happen when I'm carried off to the old gits home.