Illegal Touching

[ThomasG]

2nd and 12 from the A20.  A12 throws an pass that is caught by ineligible A50 at A) the A15 or B) the A30.  In A) the foul for illegal touching is from the previous spot with and a loss of down, making it 3rd and 17 at the A15.
In B) the defense has two options: Enforce the ineligible downfield from the previous spot and make it 2nd and 17 at the A15 (down goes over) OR enforce the illegal touching at the A30 making it 3rd and 7 from A25 (loss of down).

I cannot find support for what I've been told (from someone who should know better) that Illegal touching is always a spot foul (like an illegal forward pass is).  But since I'm asking (and I think I should know better also) I guess I might be just as wrong if not wronger.
Do I have this right?   All opinions are welcome.  Thanks

[bama_stripes]

For (B), either penalty will be enforced from the previous spot, since that’s the basic spot on a loose ball play.  Of course, you’re going to “require” the defense to choose Illegal Touching, since that carries a LOD provision.

3/17 from the A-15 in both scenarios.

[Fatso]

Are any eligible receivers in the area?  If not, then it's an illegal forward pass (intentional grounding).  You cannot have illegal touching on an illegal forward pass. 

[bossman72]

No, you can't choose an enforcement spot unless it's one of the exceptions like a tack on for a kick play or a foul on a scoring play.  This should be previous spot enforcement in B.
Given how the rule is written though, I can see why people get confused.

[VALJ]

In B) the defense has two options: Enforce the ineligible downfield from the previous spot and make it 2nd and 17 at the A15 (down goes over) OR enforce the illegal touching at the A30 making it 3rd and 7 from A25 (loss of down).

By definition 2-4-2, touching precedes catching, so the illegal touching happens during the loose ball play as well.