Typo in timer constants

These need to be either `* 1.0E-9` or `/ 1.0E9` to convert from microseconds. I think the effect of this would be that the timer units were wrong so some progress updates would not run at the correct interval. I found this because I was checking performance of some other code and it because clear that I wasn't getting the expected units.

The test is totally :poop: but I wanted to see what would happen with CI. We can drop that commit before merging this if you find it totally offensive (which I kind of do).