It's definitely a problem, but it's definitely not just a Microsoft problem. I remember my ASUS TF201 tablet where they designed the thing with an all-metal back. I'm sure everyone here knows that radio waves don't penetrate metal all that well (hence the SP3 has a plastic strip across the top where I'm sure the antennas are located), and the way that the TF201 was designed ASUS _never_ managed to provide workable wifi. Apple is also notorious for releasing notebooks with wifi problems.
I'm not trying to give Microsoft a pass here, but I'll say that they're working faster on providing a solution than I've seen from some other manufacturers. So far I haven't seen them making excuses and refusing to acknowledge the problem--quite the opposite, in fact.
I thought your name looked familiar. From the Transformer Prime saga on xda..lol prime was a great device. Just that WiFi performance was affected by all metal back.