It's possible to sell these above 1.33.

http://www.tf2outpost.com/trade/14025060 sold at 1.66

http://www.tf2outpost.com/trade/14009245 my trade, just sold for 1.55

http://www.tf2outpost.com/trade/13548393 selling for 2, offer of soldered sensei + 1 rec (1.55)

http://www.tf2outpost.com/trade/13695558 selling 1.55, sold out

http://www.tf2outpost.com/trade/11711673 selling 1.44, sold out

http://www.tf2outpost.com/trade/11477441 sold at 1.44

Yes, there are still trades out there for 1.33 refined, which is why that is still included in the range.

Also, 1.33 seems to sell quickly in some cases

http://www.tf2outpost.com/trade/14031704 sold within 2 hours

http://www.tf2outpost.com/trade/14029623 had it listed at 1.33, sold within a few hours

http://www.tf2outpost.com/trade/14029597 sold within 1 hour

http://www.tf2outpost.com/trade/14029372 sold within a few hours

http://www.tf2outpost.com/trade/14023963 sold within 2 hours

Not enough data for 1.66, so 1.55 is the high end.