you are trusting tygxc's word on this, which as we know is a grave mistake.
again, read the paper instead of taking his word. tygxc literally could not be more wrong in this assertion.
in addition, trying to study for a number of positions with the addon of "without promotion to pieces not previously captured" is functionally useless.
theres literally no reason why that could be considered, as it would just introduce more variables to be taken into accont, while in addition not matching any sort of realistic playset.
""If promotion was illegal."
++ No: if underpromotion to a piece not previously captured were illegal."
how about you actually read the paper of the calculation. nowhere do they mention the distinction to a piece previously captured. man up and admit being wrong.
Nowhere do they mention it, but they should. I think @tygxc is right on that one.
read the paper. dont just control-f "promot", look at the actual math they are doing. they literally do not account for any promotions happening of any type.
they are explicitly doing calculations on the base set of chess pieces without any promotions
this is more of tygxc trying to appear reasonable but in reality being completely wrong.