I agree…

I don’t think this is a real problem that needs solving; or I at least think it’s a problem browser vendors should solve, but lets over engineer it while still trying to keep it simple and usable…

What I might do is something similar to what you’re suggesting. I would have the anchor tag be a regular old anchor tag. Then, I’d highlight the heading (maybe just temporarily) at the same time. I’d use CSS if I could figure that out or JS if I couldn’t. The end result would send the user to the normal place and flash a highlight on the heading for users with JS support.

Keep it simple, but over engineer it to make whoever requested this happy.

Edit: After re-reading your response we probably aren’t talking about the same thing, exactly.