No, it is worth something.

A virus isn't really alive, it a machine made of biological material. Think of them like Legos. Blocks from set A can interact with those from set B easily, if they are in the same container. Because of this modularity, they can mutate faster than most things do, much faster than I would have once given them credit for.

The trick is, (a) getting both strains in you, and (b) having your body not knock out any mutant versions, and (c) having a mutated strain that actually amounts to something.