The way I see it, any pirate can stand there and heal you, so doing it yourself isn't much different. It just enables you have less dependence on friends who would probably rather be taking care of their own business. And it's different from invincibility because, well, you can still die.
I can see how it might be construed as "cheating" but I don't consider it so. If I thought it was cheating, I wouldn't do it.