Do it!!! Use Wendler's "I'm not doing jack sh!t today" template - for when you are mega crunched for time, life is happening, or you just don't care about training at all. You storm through the doors of the gym, blast through your main sets pretty much only resting fully before the PR set, crush that and walk out. Boom - 30 min, probably in street clothes, and you get to keep your strength progress moving in the right direction.
You can't do this on the reg and expect good progress, but once in a while won't be noticeable, but it will allow you to stay strong. I had to more or less do this Friday. Came in, hit my competition squats, my oly squats, and when I was getting tweaks on my pause squats (a recurring issue) I said F it and did 5 sets of heavy cable abs and walked out.