Does not compute.
What do you think the bug report feature is for if not to tell them of bugs. Sitting on your hands and expecting them to know about every possible bug isn't going to help anyone. From the second half of your first sentence I would expect it to be something that anyone with eyes would notice upon logging in, not what appears to be an edge case bug.
Just an FYI for the future, there is a new Bug Reports section for this.
All that said, good catch, it sounds like it could be exploited for crazy free heals. Hopefully it gets fixed soon.
I found about this bug when I was levelling that character and it didn't seem to me, at first, that it would be harming anyone since it help me level.
But then I duelled with a friend for fun and realised its potential and the harm it can do in pvp ( I am not a pvper mind you) and that is when I saw it as something that needed to be addressed.