It seems to me line will twist easier than any swivel.
ive always thought this also. even with a fancy schmancy ball bearing zero friction expensive do-dad, the line will twist before the swivel will spin.
i dont use swivels for that reason, however, i also tend to stay away from spoons and inline spinners like mepps for that same reason. just makes a nasty mess. if i troll spoons i use a small bottom bouncer as a weight a few feet out front to keep the weight away from the line so that the swivel actually will be useful.
I use the more expensive barrel type w/ better snaps because of the smaller profile. I have no idea if one is better that the other. Sure, lures spin while being cast but line twists that need attention come mostly from snagging a branch or little bass that kinda feel like the bottom and lakers.
I honestly don't think the ability of a swivel to spin matters. When I get snarls I cast and reel in, stop at 6' or so and let it spin past neutral, cast again and do the same thing until the spin is gone. (Letting line out and paddling never worked for me.)
It seems to me line will twist easier than any swivel. A few casts work for me but I'd love to hear other opinions.