My bigger is better comment was referring to the 1 hp power feeder vs the 1/4 hp feeder.
I think you are thinking a little different than I do regarding the difference between the jointer and the planer. The way I see it is the difference between the 2 is the reference surface to the cutter head. On a planer the reference surface is your table with the cutterhead opposite it so it will make anything that passes through it the same thickness. With the jointer the reference surface would be your outfeed table / fence. Therefore if your powerfeeder is positioned over the outfeed table it works very well. Not every board is going to be straight in one pass and it is not a replacement for working by hand on a difficult board. However the safety and speed are worth it with a project like this. Especially when every board that was really warped got cut in half before ever going onto the jointer.
For my purposes I will eventually have a powerfeeder that stays on my jointer, I was thrilled how well it works, that is not to say I will never spin it out of the way to do a board by hand.
Steve