Just to add to the confusion, CA is right, any spice blend is a "masala" by definition and "curry powder" is quite different to "garam masala" Yet I use a "spice mix" that requires both "Curry powder -2tsp" and "Garam masala -1/2tsp"
The spice mix is required near the start of the dish, so if what the general belief is, is true, that garam masala loses it's flavour (pungency) over the full length of the dish, why would it be included in the "spice mix"

I have used garam at the end of a dish but like Jerry, I think it takes me away from replicating BIR dishes. It was only a pinch, but you knew it was there!
Ray