I wonder if, maybe, it might be a middle of the road for someone (like me) that does not want/enjoy fast progression...but does adhere to the more modern gaming sensibility that all PCs are created equal and should be leveling together all at the same time..
All Created Equal would be 'everyone starts at 1st with 0 xp'. Having new pcs come in at party level is All Are Equal, pretty well the opposite.
I use both, depending on the campaign.