The statement that technique trumps the tool is 100% spot on IMO. I'm no expert sharpener but I've found that to be true with about any skill or hobby. My guitar sounds like a different instrument in the hands of someone who really knows how to play.
I believe regarding sharpening this is true when using stones or the EP. My preferred progression is to use the EP for profiling an edge and then finishing the edge with bench stones. I could get a crisper edge using bench stones and very light strokes on the last 5 strokes or so. Then I decided to experiment and practice using the EP for everything. I have a set of Shapton glass stones for the EP from 500 - 16k and after practicing and paying VERY close attention to using light strokes just like on bench stones I've been able to get super smooth, very sharp edges using only the EP and even stropping with it. I have 4 or 5 balsa strops for the EP with a variety of grits of sprays. I also have some nano-cloth and roo strops for the EP and they will do just a good a job using the EP as they do on a bench stone. IMO the EP is a great tool and capable of providing the superior results some crave and strive for. It's just amatter or forcing yourself to use it with the same dedication people use to master bench stones. It's the technique that is the determining factor. I believe the key for finishing an edge no matter if you use an EP or other "system" or if you use bench stones is to use extremely light strokes. I've been hearing the very experienced folks say this for years but it wasn't until recently that my hard head realized it.
Having said all that I prefer to use bench stones for finishing an edge. With the EP I like to profile the edge with a known angle that is consistant. This is one area I have not forced myself to become better at. That will probably be my next project. If I ever decide to develope more skill using bench stones only I'll put an bevel at a known angle with the EP then try to keep the bevel as flat as I can and at the same angle using bench stones. Ive done this a time or two and when the bevel is flat it's easy to feel the flat spot on the stone. However, after a few strokes the bevel is getting convexed and I can't feel the flat spot and have to keep the angle consistant on my own. I think that starting with a "known" and trying to duplicate it or maintain it is a good training method in a lot of skills. Of course I'm very new to getting edges really sharp so my opinions about things change quickly.