DeStress encourages the plant to emit root exudates that feed the biota in the soil. It originally was designed to work with Roots! but since then formulas have been adjusted, and it's not "necessary" like it was. If you've been doing it twice a week, I'd skip it for a couple weeks and let the soil critters populate all by themselves. If you see any weakness though, give 'em a shot.
In any case, twice a week will cause trouble. I think that must have come from 1/2 strength recommendations for weak plants. It was never officially recommended. Doc and Duggan don't use it at all unless they're stressing the plants. Duggan only uses it while he's training/supercropping.