On a shorter board I would think it might be easier to pearl the board? Especially in super choppy conditions.
All other things being equal, I would tend to agree.
They do seem to ride vey well on the tail though and keep the nose clear, although it would probably need a video of them actually pushing the board in race conditions and chop to know for sure.
They look well in control here - although these may not be the same as the Underground model, but they sure look short.