OK here's the answer to what GSes was talking about... the all-time worst ERA's of pitcher who had a K/BB ratio of at least 17:4 with at least 200 IP to get rid of small sample sizes:
Brad Radke 4.49
David Wells 4.14
David Wells 4.11
Jack Lynch 4.09
Greg Maddux 4.02
Brad Radke 3.94
Jimmy Key 3.88
Shane Reynolds 3.85
Bob Tewksbury 3.83
Scott Sanderson 3.81
That's all-time - over the past 100+ years, the worst ERA's ever. Of the 131 seasons of a K/BB that high there have been exactly 0 with an ERA of 4.50 or higher. And notice all of the guys on the top of the list are finesse pitchers who don't get a lot of K's. Not the case with Vazquez. This will not continue the way it has, there's absolutely no reason to believe it will.
As for my formula, I'll go punch in the numbers...
Given his K's, BB's, and HR, that is what his ERA should be. This is a great buy-low candidate if I've ever seen one.
"Jack, will you call me, if you're able?"
"I've got your phone number written, in the back of my Bible."