I'm not surprised that it's been suggested before because it's obvious really. But unfortunately whether it's a lack of initiative, foresight or funds it probably won't happen in the next 5 years.
I do believe that even the Airport could open and operate this successfully on it's own but would probably ask for a cut in sales going towards NIR. Although it would be better if they done the project joint.
A halt is exactly what it would be and I'm sure there is other avenues of revenue than just tickets. They could stick an ATM and a few vending machines in it to recieve rentals. I hear you can get around 15-30k per ATM space per annum..
But perhaps with passenger number growth at BHD, and the need to cut congestion, management at the airport may decide to self fund or seek funding in the next budget period after 2015. Fingers crossed!