Best of Series of Matches?

With Punk/Bryan this Sunday on a nothing PPV that might threaten the record for lowest buy-rate for a WWE show ever, it got me thinking.  Why doesn't WWE do any best of x series like we've seen in the past?  Obviously the argument against is that there is no pay-off until the last match and with a smart crowd, the results of each match are tough to keep interesting, and you need 2 good workers as well.  But, the way WWE books with even-steven booking anyway and frustratingly no pay-offs most of the time, doesn't it seem like this would work really well with the current product?  You couldn't do it with the Cena or Lesnar, but an upper card series with 2 good workers could be great and could elevate both.  They essentially did it with Bryan/Sheamus, and that worked out well for both in my opinion.  There is no way they could do a 7 match series, but 3 or 5 with at least one of the matches on RAW seems like it would help the PPV, RAW, and those involved.  How great would a Punk/Bryan best of 5 over the summer have been?  They essentially do this anyway without the playoff series type of drama…with Vince's desire to be more mainstream, doesn't it seem like he would want a playoff type of format like the major sports?
-Rusty Rae

They tried it in 2004 with John Cena and Booker T and it wasn't great, to say the least.  And there was the Hardyz/E&C series in 99 that worked out pretty well for them.  So it's been done.  But here's the thing — fans are conditioned to know that the payoff would have to be on PPV, so if you're doing a best of 5 and Bryan wins the first two, then they know that Punk has to win the next two in order to get to the PPV blowoff.  So for me it would kind of deflate the suspense and defeat the purpose of saving the big deciding match for the PPV.  But at least we'd know what the main event was going to be for a few shows in a row, so that's something.