There has apparently been little talk between Punk and creative regarding a way to write him back on TV. If I were at the head table of creative I would propose the best way for him to come back is just before Summerslam...and to come back to take down The Undertaker.
While the sheets have been saying Undertaker is expected to work with the Shield, I believe the only worth while way to make Punk relevant right away (other than getting HIS title back) is to come back and have Taker put him over at Summerslam. This gives Taker an opportunity to actually put someone in this generation over, considering it is impossible to do so without tainting his WM streak.
Maybe promote Taker's return with a blockbuster RAW tag match between The Shield and the Brothers of Destruction and have Punk cost Taker the match (this could also take place at Summerslam, though I'd like to see Punk vs. Taker at the PPV instead). Punk is clearly missed right now and I think the product is dull as fuck without him. So...what are your thoughts and how would you like to see him come back?