Putting aside the inevitability that Vince is going to have Brock lose to HHH at summerslam.  Wouldn't a more interesting move – that works with his limited appearances – is for Heyman to tell HHH that Brock will face him at summerslam only if the Board of Directors puts Brock in the MITB match with Cena/Big Show et al.  Then let Cena/Show take eachother out of the match (because heaven forbid they just put Brock over the entire field strong), and have Brock get the briefcase.  Then he/Heyman can cut a promo saying that now that they have a guaranteed title shot there's no need for Brock to appear again until he cashes in and wins the title and that will be at WM29. 

Your views intrigue me and I wish to subscribe to your newsletter.  You could also have Brock call Cena a chicken until he puts the briefcase up in a match, ala Edge-Kennedy, and then Brock beats him to get his win back and gets the briefcase.  But you're right, giving Brock the case would be a GREAT idea, because it makes his eventual return worth double as far as importance.  Plus you know the champion would be shitting in his pants waiting to see if Brock shows up and cashes in.