I use it a lot, probably more than Jerry did, but probably not too far off from how I'm hearing his use of the delay.
I hear Jerry using delay quite a lot. Remember that he's using the ADA that is connected to a pedal that is controlling the dry/delay mix and one pedal that is control the delay time. On his slide work and on most big overdriven solos, Jerry's is bringing in subtle amounts of delay with short delay time. Then you've got the longer delays on songs like Wheel, Crazy Fingers solo, Stella and Ship of Fools solos, etc. I also like to use the delay with in-tempo repeats on songs like Shakedown (e.g., Shakedown 9-18-87), where the delay is used to create some funky in-tempo repeats.
Overall, I keep the dry-delay mix fairly dry heavy, and I use a delay pedal that has tap-tempo and an expression (to control mix): http://www.tcelectronic.com/flashback-x4-delay/
Although I use a pedal switcher with my effects in a rack, I keep the delay with the switcher so that I can control tap-tempo and take advantage of three presets. My new switcher will control the presets via midi, but its not a pedal that is well-equipped for controlling tap-tempo and expression pedal remotely.