Awesome timing on this article, this is almost certainly exactly what's slowing down a big server workload I run when transparent hugepages are enabled.
We tried experimentally enabling the THP feature in the latest kernel but it made things *much* slower, which seemed really mysterious. Now, knowing that the kernel is unnecessarily blocking processes on writing some pages to disk explains the whole issue. (Note: no USB sticks here; normal hard drives are already slow enough for me...).
So yeah, that argument about how it's desirable for long-running server workloads? Not so much.