Ahh yes, for a new pool or plaster job, the curing of plaster or any other release of calcium hydroxide into the water or conversion of calcium hydroxide into calcium carbonate raises the pH significantly. The TA rises as well so acid addition just gets you back where you started. The CH will rise if calcium hydroxide gets into the water or it won't rise if it stays in the plaster surface and just takes up carbonate.
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The Borates (usually from boric acid) cost extra. Some people who have dogs that drink mostly from pool water prefer not to use Borates for extra safety (see Are Borates Safe to Use?). Otherwise, there isn't a downside. They are most useful in SWCG pools not only for slowing down the rate of pH rise, but also helping to reduce calcium carbonate scaling in the SWCG cell. They are optional and would let you add acid less frequently, but probably not lessen the total amount of acid you have to add over time.