If you are worried about bather load then you need to test your water more frequently. You should use the FAS-DPD chlorine test as that is VERY accurate, goes from 0.2 to 50 ppm for both Free Chlorine and Combined Chloramines.

Unless you are aware of a DEFINITE contamination (fecal matter) there is no reason to shock your pool just to shock it.

If your FC level is consistently good, with no drops, and your CC level is consistently 0 or at least < 0.5, you are fine.

Bather load can and will drop FC--so the frequent testing is how you control for it.

But if your FC drops to 0 or very, very low, or you see algae starting, or there's a known contamination, then by all means shock your pool up the maximum for your CYA level.

Check the "Best Guess" table for the shock level appropriate for your CYA (stabilizer).