Quadrophenia and Tommy were doubles, so would work out to 20 and 19 minutes a side respectively. About right.
I could certainly make a decent case for cutting The Song is Over from Who's Next to bring its length down a bit. I suspect it's on the long side for a single LP because it was...
Somewhere I read a comment by Pete Townshend that 18minutes a side is the most you want to go up to for a rock album before the sound quality starts getting worse.
You want a pisstake of an album length, try 60s Beach Boys albums. All Summer Long is only 25minutes in total.