Where in BC do you live? I know there are areas with lots of rain and also areas that make the Salt Lake Valley seem damp.

Do you know what kind of grass you've got (the grass you want, not the poa triv/annua)?

I'm on the South Coast (in a suburb of Vancouver) -- quite rainy in the spring, winter and fall, although summer is drier. The area is, however, slightly shaded, so it doesn't ever go bone dry (I rarely have to water it).

The rest of the grass is perennial rye/fescue mix, and from my experience there's not alot of "creeping" into bare spots, so I doubt there's much creeping fescue there.

You've probably got mostly perennial rye, which is a bunch grass. If I were you, I'd pull the weeds and put down more seed in the bare spots. Perennial rye germinates very quickly so it should be able to out-compete the weeds if you get the seed down right away.

Thanks. I'll do that.