umm I dont if this is definite, but from experience, first record a few vocal 'double' tracks, try to get your vocalist to imitate the original as close as possible to avoid syllabic confusions, then lower their volumes considerably till they dont compete with the original, that will take care of thickness factor, then just add reverb as an insert to all your tracks to provide the space. hope that helps.

Thanks!
I will try this

From my psycho acoustics notes:

Distance is determined by 4 factors
Perceived loudness
Direct vs reflected sound ratio
High frequency absorbtion
Delay, not only as an effect but on the sound itself

So you can:

raise the aux send to the reverb.
another type of reverb, different settings, add another to the one you got.
another setting (volume, EQ, FX, Panning, doubling) of the vocal parts.
track with a different mic, preamp, ambient mic technique.

Try increasing the pre-delay and HF damping on the reverb you are using.
Try a different balance in the vocal parts.
Though I am not familiar with Pink's song it could well be that the exta parts did not have much reverb on them in the verse, but they get that in the chorus.

Reverb as an insert on the individual track is a way, but when working ITB it is a waste of resources (CPU cycles). When more than one track need the same effect, use an aux track. Send signal from the tracks post fader to an aux track.

Rock on!!

its pretty common to preform production techniques to make the chorus stand out in contrast to the verse.

There are countless things you can do. And every one has their preferred methods. I for one like to use some digital delay to create a chorusing effect. also bumping up the presence in the EQ helps allot to make it really stand out. I tend to make the pre delay on the verb longer as well. not much, but it gives you the "in yo face" type feel to a powerful vocal delivery. even if its very subtle.

there are plenty of things you can do. try out some ideas for your self.

Thanks!
I'll keep on trying