Yes, and there are tons of reasons why you don't want two dissimilar GPUs doing the same workload. Imagine a situation where you pair an Intel integrated GPU with the latest and greatest from nV or AMD; what exactly is the Intel GPU going to do to improve performance? Even in situations where the GPUs are more evenly matched, like for example in a Laptop, you're still going to be limited to what the slow GPU can do.
There are other, more useful ways in which to utilize the ability to operate two GPUs at once, like doing GPGPU work on the weaker one, but even there, the sheer amount of possible configurations will make the task of testing a game even harder than it is right now.
