We've been racing the last 10 or so years with only 2 of us going. Personally, I find a 4-wheeler mandatory. We go to many tracks where we have to push against the stagger to the push-off lane, and with 1 person pushing, it can be quite a chore, if not near impossible. With us being notoriously late getting to the track, we NEVER get a spot near the push-off lane......
Hope this helps!