Both Epic Eldritch Blast & Epic Pact Dice require warlock level 12 to take. Acolyte of the Skin lets you take dice as feats independently of warlock levels (just like monk can take their upgrade feats with splash builds). The problem is as a warlock, one's blast damage will drop hard if one doesn't take the 2 epic level feats so it limits AotS multiclasses to 12 warlock builds if they want to use blasts. It would open up a ton of build options if those 2 feats could be ML12 warlock / "Ultimate Pact Attunement feat" for their requirements. There's already a feat tax in taking them all, so it's not free damage; it would just make for more build choices.
Edit to reflect Ahpook's suggestion (for those who might not read thru the whole thread).