I don't ride, but I do go out in the back country with people who do. No one I know snowshoes out there. They are way to slow and take too much energy. Skinning with a split is very efficient, but the change overs from skinning to riding and vice versa are noticably slower. It is important to have that routine down if there are multiple laps to be had.
For skiers as well as boarders, there usually is some performance loss with BC gear. Even the stoutest AT boots are not as ski oriented as my alpine race boots. That is just the price to be paid for good backcountry travel. You spend 90% of your time going up, so do it efficiently. I have no doubt you will loose some board performance going to a split, but it will beat post holing or snowshoeing. I have one friend who Macgyvered some small skis with skins permanently attached for the climb and carried his powder board on his back. On the ride down the 120cm skis were on his pack. It is a little heavier that a split but more efficient than snow shoes