may you

I have often seen it written: "May you help me?".
I was sure that it is not correct; however, I had not found a rule concerned with this.

We do not use May you... or shall you... to make requests.
We use may, might, and would with be willing to, be prepared to, etc. to make very tentative offers.

We can use would and might with willing to, etc. to make requests:
Might you be willing to do the job if I offered you another ten per cent?

So, would you be, please, kind enough to refrain from writing: "May you help me".