Yes. Instant messenger is fine, although a small problem tends to arise when you use different forms of it or one of you doesn't have it. Sure, it's great if it works, but it isn't guaranteed to.

And sending PMs to multiple people would make it much easier to PM spam than to have a lowered limit. One person every two minutes or five people every five minutes. Difficult decisions...

All I know is, I'd like SOME degree of leniency, either by amount of people or amount of wait time.