This isn't the best video, but watch this:
Essentially, dominos are faster, stronger, and are way easier to align than pocket holes.
I say that... ironically... as I just came in from drilling pocket holes on a project that would have been a bear to clamp.
I think they all have their place really...
Thanks for the video. The way I saw it, the pocket holes were the fastest, however they did produce an ugly product. - He could have put the pockets on the inside, but it still would have had holes that were visible. They wouldn't have worked on your cool box. He also took a couple minutes to screw the jig to a board. I leave my pocket hole setup attached to a table top that I can clamp into my Jawhorse or bench vise and be drilling pocket holes in about 15 seconds.
Sounds like the Dominos self align much better than pocket holes, which as he said you have to clamp to make them align perfectly.
Another question: How difficult is it to get the two mating dominoes to match? - especially when you have multiple dominoes along a joint.
One of the problems with the biscuits was that the blade always wanted to "walk" down the board as the blade cuts in. There were a couple sharp pinpoints that helped hold it in place, but they had varying effectiveness on different materials. It didn't really matter on biscuits, because they don't align along the axis of the biscuit, the only alignment is 90 degrees to the biscuit.
As you point out, pocket holes are self clamping as well. I find this to be their best feature. I don't build fine furniture - I build quick and dirty shelves and cabinets, and I like to keep moving.
The other thing I like about the domino machine is the dust collection. When I was younger a woodshop was a dusty place - I guess modern technology has made that not so much a necessity anymore. I think I'll try the domino out at the woodworking store next time I go in there.
Anybody need a biscuit machine? - I'll throw in a new box of biscuits...