You are correct that some of these troops have Ranger tabs, but that they are not in Ranger assignments. Those are limited to the regiments in USASOC.
However, the point of the supporters of these men is that they have been prodded to use these techniques by the Assymetric Warfare group, which has SpecOps ties. Some of them might well have been in Ranger units or have qualified as Rangers and been taught these special techniques as well.
I would think that any sniper is told not to speak of his mission, and infantry units do have snipers.
It is a fact that Special techniques enter into regular line units because those units are regularly cross-fertilized with officers and NCOs who come from SpecOps units.
IED material drops (in specific AO) are one thing - No one has ever been prodded to place AK-47s on KIAs (by AWG). Though, I am in no way suggesting this is in fact what happened for certain (this soldier could simply be lying for various reasons).
Earning a Ranger Tab (while honorable) is different from serving in the 75th and being a Ranger.
Again, I know JAGs are costing us in this WOT. They are in fact making guys triple guess their decisions constantly (and in fact, may cause some to make stupid decisions on righteous kills to begin with.....by needlessly manipulating evidence).