You're my second surely reliable source for that tip. AND you're in the interweb so it must be true!
I know you were smiling when you said that, but there actually are at least two ways to gain resistance to poison oak by ingesting it, or at least coming close to ingesting it (eating the damn stuff isn't one of the ways). The Miwuk Indians used to make a very (very) weak tea of it and apparently gained resistance that way. Another classic method is to drink the milk from goats who eat poison oak.
Or you could just gain resistance the way I did: get awful, terrible cases of it over the years until it gradually doesn't affect you so much.