THEME:   first word of a phrase is repeated making an unusual 3-word phrase   
GOOD ONES:     Signed agreement mailed by someone in prison?   CON SENT CONSENT   
Backs a fashion venture?   INVESTS IN VESTS   
Songwriter's dream?   FORTUNE FOR TUNE   
Deer guy   STAG [few days ago it was "Deer girl" for DOE]   
One unlikely to bring home the bacon?   VEGAN   
New newts   EFTS   
Dessert conveyance   CART [unless you read it "desert" and thought it was a camel]      
BTW:   
To riterate:  
ERES is not English, but there is a song enjoyed here: "Eres Tu."      
Authorize two bros' get-together?   
MANDATE MANDATE [but "to mandate" means "to order," which is different from "to authorize" --- I am 
authorized to enter the vault but not 
mandated to enter it]       
A trip down memory lane with Bob Pettit (not Andy Pettite), quite a shooter in his day; and Richard Egan in 
A Summer Place, quite  a scandal in its day.      
RATING: 
 
 
   Three grins = Loved it; Two grins = Enjoyed it; One grin = A bit bland for my taste; One teardrop = Not much fun