For real, like no one else goes to work because they want money...I'm sure you all do it because you just love sitting in an office!
To the arrestee, I wouldn't get too upset about anything yet. A DUI is a fairly standard defense, I'm sure he's done hundreds of them and this is nothing out of the ordinary. There isn't a whole lot of prep work or background investigator/evidence collecting to be performed. I do defense work as well here in NY and I hate talking to my clients as well. It isn't anything personal, but to him its just another case (that he wants to win, remember).
IF something does go wrong, you should report him. I would give him the benefit of the doubt, however, as he was like this before with you and ended up getting you off the charges. Sounds like he's a prick, but a prick that gets the job done.
If the cop never saw you actually operating the vehicle, he is going to have a hell of a hard time proving that you actually drove the car drunk. I would subpoena the guy who was driving your car and have him testify that he was driving. I would also subpoena the records of whatever place brought you gas and the guy who brought it.
There is no law against sitting in your car drunk. The key element to DUI is DRIVING. Your case sounds like you have a pretty good chance of winning. Good luck, let us know, and I'll forward you my bill 