Here's a headline from today's New York Times:
At Particle Lab, a Tantalizing Glimpse Has Physicists Holding Their Breaths
I've written before about subject-object agreement, like "Users who experience dizziness should call their doctor."
The bottom line is there's no right answer in most of these situations. But I bet that about 99 out of 100 editors would have made "breath" singular -- a collective concept -- in that NYT headline. " Breath" isn't usually treated as a count noun. It's more of a mass noun. And if a nation can breathe a collective sigh of relief, can't breath be as collective as sigh?
Odd choice. Not wrong, per se. Just odd.