In my mind "Quick Synthesis" implies not being as careful and cutting some corners to get stuff done quicker then you really should. And if youre using your skills(and only care about completion and not HQ) then you can guarantee manual completion of synths well above your level fairly easily. And plus, most of the dedicated crafters can complete the 0 star level 70 recipes(if not harder) with full quality going from normal mats 100% of the time - so should they be able to QS up a full stack of HQs too?