Since D76H has no hydroquinone in the formula you've given, how does it "elegantly avoid the problem of hydroquinone being activated as D- 76 changes pH as it ages"?(posted 8365 days ago)The reason hydroquinone is used in D-76 is that it is super additive with metol. Hydroquinone does not readily adsorb to the silver halide crystal except in a really high pH solution (10-11).
Conversely, metol easily adsorbs to the silver halide crystal but rapidly runs out of electrons. The hydroquinone is used to feed electrons to the silver halide crystal through the adsorbed metol molecules.
How does D-76H equate to this super additive chemical activity without the hydroquinone?