Well, after I posted, I applied the LAA utility to both SimCity4.exe, and the launcher, and it works - as in loads OK, anyway. It's apparently smoother but I did it with a few other changes, so hardly scientific.
There's a list of SC4 reliability improvements here: http://attendthis.net/cba/index.php?/tutorials/article/4-simcity-4-getting-the-best-performance-and-eliminating-ctds/
Amongst them:
and
Can you tell me if the launcher supports these? My guess is that #2 is independent of the launcher, i.e. I can flag the main EXE (or the launcher?) myself, but I don't know for sure.