I asked them during 2 separate, unrelated, support calls and neither tech knew the answer. One put me on hold over and over and spent 25 minutes trying to find someone he worked with that knew the answer but was not able to get me a definitive answer.
As I stated, incidents like that are the reason I lost faith.
But on the chat yesterday (as futile as it may turn out to be), I told the agent to find a technician or engineer or whomever to get this answer. I mentioned that just as it doesn't make sense to just say "USB support" without indicating 2.0 or 3.0, neither does it make sense to just say "DisplayPort" as there are significant improvements. That point seemed to have resonated, but then again, the matter ended up being "escalated." To me, this isn't something that needs escalation; doesn't anyone there have a schematic diagram or something?!
In another post, someone mentioned that the 1.2 specs were released in 2009 and that it wouldn't make sense that MS would use the old spec in a 2013 product. But my response was, "you never know," because you who knows for how long this thing has been in R&D and other technical factors that may drive them to use 1.1a. However, my personal and selfish recommendation would be even if they started with 1.1a support, then when 1.2 came out, they should have adopted it, due to Windows 8's robust support of multiple external displays and the Surface Pro's single DisplayPort.
As you stated, it's unfortunate and, so, I've started to prepare to bite the bullet by ordering the accessories necessary to connect both of my monitors to my USB hub. My preference would be to use the DP 1.2 daisy chaining capabilities, but it seems like I'll have to wait for that. Oh well! I just hope that both monitors do not eat up too much bandwidth away from my USB-Ethernet connection.