I've done in 3 days...and yes it was enjoyable.

The key is getting to Lower Rock Creek Crossing. We crossed NAP, which I prefer, and from there it was all down hill...literally. The following day we ended up at he Tarns above Guitar Lake very early in the day afternoon and kick backed and relaxed. Day 3 started at 12:30 AM and we were on the summit before sunrise and showering at the Portal Store by 2 PM...a shower that no longer exists.

It's was enjoyable because I was in great shape. This itinerary is not for a couch potato with a heavy pack.