You can find lots of talk about slower (looser) twist rates among the benchrest crowd, many saying the same thing Gibbs has stated...albeit a bit differently.
A 1:12 or 1:14 twist rate on something like .308 Winchester allows a hotter powder load with heavier bullets, without worrying too much about over pressure issues.
Had a retail customer that bought two of the CZ 527s, one of the carbines and a varminter. He was pulling his hair out trying to find one load for both, called CZ, and they stated (IIRC) the carbine has a 1:8 twist, the varminter a 1:12 twist for these reasons.
Apparently the Europeans believe the theory too.