I would say that good training will likely lessen the behavior, but he may not ever be completely trustworthy. We had a beagle like that and beagles are notoriously stubborn. I don't know about this breed, however. 
The first thing we did was put a leash on him and just let him drag it. Then when he bolted, we had something to drag or step on just for his own safety and our own sanity. No substitute for training, but it keeps him safe while you're training, and really if you step on that leash while they're bolting, they get a correction all of their own making. Without success, it is easier to train.
The next step is to teach him some basic manners. If he recognizes that you're the "alpha," he's more likely to recognize that you get to cross through doorways first. So all training will actually help with this a little if he learns to respect you. And you can make him sit and wait for you to cross every single doorway in your house, whether it leads outside or not. Then you work on a really good sit, stay, and do it in front of an open door (while you have control in case he makes a run for it!).
I don't know what it takes to actually trust a dog to not take advantage of the open door, but this should at least make him hesitate and not be charging between your legs while you're trying to do some contortionist maneuvers to get out a door without leaving a big enough gap for the little guy to slip through.
When I was a kid, my parents had a dog that would hide under the couch and wait for the door to open. Then he was gone. At least until he learned how to open the crank windows in the front room. Then there was no keeping him in.
The first thing we did was put a leash on him and just let him drag it. Then when he bolted, we had something to drag or step on just for his own safety and our own sanity. No substitute for training, but it keeps him safe while you're training, and really if you step on that leash while they're bolting, they get a correction all of their own making. Without success, it is easier to train.
The next step is to teach him some basic manners. If he recognizes that you're the "alpha," he's more likely to recognize that you get to cross through doorways first. So all training will actually help with this a little if he learns to respect you. And you can make him sit and wait for you to cross every single doorway in your house, whether it leads outside or not. Then you work on a really good sit, stay, and do it in front of an open door (while you have control in case he makes a run for it!).
I don't know what it takes to actually trust a dog to not take advantage of the open door, but this should at least make him hesitate and not be charging between your legs while you're trying to do some contortionist maneuvers to get out a door without leaving a big enough gap for the little guy to slip through.
When I was a kid, my parents had a dog that would hide under the couch and wait for the door to open. Then he was gone. At least until he learned how to open the crank windows in the front room. Then there was no keeping him in.
