Normally it would not be a problem for me, as I use only the English language. In the case of changeset 3090, it s a replacement of a translate string - that has to be uniformly carried over to all affected files and the empty.po as well.
In the case of 3091, the new strings can come in during an FA release - if it was done at once, then those using non-English languages can also partake of debugging - we need as many eyeballs as possible on the code to get it up to speed. It will also help those translators in getting the strings translated well before the FA release.
Otherwise, such translate string changes should be withheld till the FA release whence it would update the empty.po as well.
A policy on this score would augur well when more than the current couple of committers comes to pass.