Oh, I don't know, Kitty's power was a lot more than standing still, and Logan understaood that selective intangibility could an astonishingly useful boost to hand to hand combat, since it always gave her the element of surprise when attacking and as a defence, not being physically solid is a tough one to beat! :)
And in Doug's case I'd say it was likely that he didn't train particularly hard in combat skills because it wasn't an area he was madly keen on being experienced in. His powers (until the body language bit was first mentioned, less than six months before his death) didn't lend themselves to combat the way that, say, Dani's did, so perhaps it was as well that Doug didn't get TOO confident in his fighting skills.