I heavily, heavily doubt this. In fact I'm willing to bet that there is zero perceivable difference with an EMG. I'll record clips this weekend.
I agree, the pickup will be a big factor but my point is the reflection from his wall will be reentering the pickup and cause phasing from a comb filtering effect. An effect that would be minimised in a treated room (probably).
I don't have this issue with my guitars at all.