The ONLY advantage to a fallaway is clearance for helical and small diameter arrows,the rest is bs as you say.
A prong style is probably a little more forgiving if you want to get technical about it.Most fallaways drop from contact with the shaft to soonbut the arrow is still attached to the string,this is an unforgiving situation.The arrow needs as much guidance from the rest as possibe.
No the WB isn't the answer,it still has contact with the arrow AFTER the arrow leaves the string.
Look at what is on MOST pro'sbows in vegas or any big shoot,they are not fallaways,they are mostly spring steel rest of some sort.