I have a "theory" about that which might not be true at all but...
After that failed Wasted Years solo when Adrian totally got lost I went to check other Wasted Years performances and to me it seems that Bruce is giving hints to Adrian. That's how I see it and if true its a very clever way to do it while making it like he is interacting with the audience.
The show in O2 to me (and let me say it it again, to me) indicates that Bruce is "telling Adrian where he is". I'm sure Adrian have a bit of Bruce voice on his Ear set.
min 3 +/-
min 3.16+/-
min 2.40+/-
You can see the same on other shows, not all but it happens frequently.
Adrian can be confused (for whatever reasons) and I very much doubt its because he cannot hear the others or because of faulty equipment...