I think the 'and then three' comment is redundant for the Knight, since six Knight-leaps in the same direction would require a board of 13 squares in at least one dimension. Hmmm... using such a piece in a variant with a larger board, could the Rook and Bishop go 'and then four,' or is three the speed limit?
Come to think of it, a piece like this with a 'speed limit' of 2 might be interesting-- the Rookwise piece would be color-changing, while the Bishopwise one would remain colorbound, but switch Alfil-bindings... hmm, I just reinvented the Panda and the Bear.