Yes, it's good to hear that I'm not the only one who needs to fall back to a wave board when the going gets tough
Yesterday, I've examined more closely the tails of my wave board and my slalom board (IS87).
I did not expect that much difference with these low volume boards, BUT there is !
The tail of the wave board has a really sharp and pointy end, whereas the IS87 has a more round end (+ cutouts of course). Then, beside being very narrow and pointy, the tail of the wave board is also very thin (small height). The latter is probably also very important to smooth out the chop.