Seems to me Miller is absolutely correct. Think of magnaporting--all those holes near the muzzle don't cause the barrel to burst. Pressures near the muzzle are very modest in most cases. The danger of really thin tubes is they're easy to dent badly and a following shot could have catastrophic results. Several good gunsmiths I've visited with tell me dents in barrels with less than .020 wall thickness cannot be properly raised without creating a dangerous condition.

John McCain is my war hero.