This question is often debated and it's never easy to answer:
Should you contact the Profile Manager before editing a profile they manage, or just go ahead and make the change?
Here's a draft of a new page with recommendations:
What do you think?
The only item I see that might be worth expanding on (possibly not on this page but linked from it) is when you say "In your comment on the change..."
My observation is that many people overlook the "explain your changes" box on the edit tab, and on a very cursory look through the help files I do not see it mentioned anywhere (although I may well have overlooked it) - I think it would be beneficial to bring (more?) attention to that box so that people do not confuse it with profile comments on the profile view tabs.
Now that the basics are settled, here's a new G2G question for a "harder case": Should you ask before making improvements to the writing style on an Open profile?