Yeah, that DirectX 12 support is super important for when you want benchmarks that show AMD cards are faster than NVIDIA ones. For actual games that people want to play, nobody cares.
That is such a pants-on-head-retarded analogy that I'm not even going to bother trying to correct you.
Iiiiiis it? If 3,5 GB of memory runs at lightning speed and the 0.5 GB of data is sitting inside the slow part, what do you think it's going to happen? It's EXACTLY like car with 1 defective wheel that's dragging it to the side and slowing it down. EXACTLY like that.