I use Dominos, and yes I have made the mistake of putting them too close to the edge and having to repair that area.

I also almost always use cauls, so when I am done, the boards are very level with the joints solid.

As Prashun said, no question that good jointing of edges is very important to avoiding gaps.

A couple of quick passes through my wide belt, and the boards look amazing.

Belt and suspenders approach - absolutely. But I'm not selling my work, and don't have to worry too much about time and productivity.