Thank you for clarifying that the question is about the gas requirements of a large on-chain exponent calculation. Actually the updated document assumes only Elliptic curve operations. It is denoted in exponent format like ๐แต instead of ๐ยท๐ but the underlying operation is the same. (Do you think changing it to ๐ยท๐ format helps? I'd be happy to do that.)
That being said, the actual gas consumption definitely needs to have experimented.