I saw two tech stops this season, the first in the final moments of Girl from the North Country, just before Winningham got to "Forever Young." When the show resumed after ten minutes, they backed up and did the entire sequence prior. Smart call, and the performance still worked beautifully.
At Strange Loop at a Wednesday matinee in June, same, only it seemed part of the show, the meta component baked in. The audience cheered and applauded until it was finally clear it was a real stop. It was quite lengthy about 15-18 minutes, but only 30 minutes in, and everything fell back into place.
"I'm a comedian, but in my spare time, things bother me." Garry Shandling