Before the Sol ner- err, the -50% Atk debuff cap, that somewhat held true.
Now though? Not at all.
Also, I hope you are aware that a slvl20 Pride weapon provides the same 10% at all times, regardless of your HP? Only the base portion of it changes depending on your HP. You seem very vehemently opposed to Pride weapons, which makes no sense unless one thinks of them being "all or nothing" type of things.