Likewise, I understand how many already extremely strong lifters could fall in love with the idea of pressing 700 lbs, even when they can do 600 or so without a shirt. I understand that using shirts is a skill in itself as is using leg drive within legal limits and various other techniques that serious lifters use to move heavier weights, but it is a natural absolute that if you can not lift X amount of weight without item A then you can not truly lift X amount of weight regardless of how trivial item A seems to be.
One common response to criticisms of equipped lifting is that the same lifters who do +700 lbs with shirts are still enormously strong without them, and maybe could do 600 or more raw, but the obvious rely to this is that if someone can do 612 or what ever clean they should accept that, that is the real number.