Yes, I don't think that works.
There's a thing called "dynamic disk". If you convert a disk into that (it's in the right-click menu on the left side in disk management where it says "drive 0", "drive 1"), then you can create dynamic volumes. Those can fuse partitions from multiple dynamic disks into a single large one. The problem is you can only use that for data I'm pretty sure. You can't boot from a dynamic volume so you can't use it for C:. I can't find proof for that to show you right now. I'm failing to answer if it works or not with my Google search.