Whippy only became fear aggressive being attacked on lead by a JRT, actually KittenSoft. She was and still is, when off lead, very well socialised and interacts regularly with other dogs. She has no choice but to interact with other dogs, we foster for a local rescue, she often has strange dogs trying to sleep in her bed, she has done since she was a puppy, she is fine with this. She panics when she is on lead a) because she was on lead when she was attacked so is often tense on lead and b) she knows she cannot get away if she needs to.
I'm aware of calming signals and often use calmer dogs to walk with Whippy whenever possible, their behavior calms down both Whippy and the on-coming strange dog, which makes things easier for all.
No, she is not currently muzzled, although at the start of our training, before I injured my arm, I used a muzzle to prevent other dogs running up to her. Ime people see a muzzled dog and automatically assume dog-aggressive and make a bigger effort to stay out of our way, even though with a muzzle she cannot hurt their dog 
She does not need to be muzzled, she is leashed and under control, if another owner cannot control their dog enough to keep them out of our space, then frankly that is their problem, as my dog is leashed the law is on my side, although given that she is the size of a large cat and weighs as much as wet dish rag, there's not much damage she could do anyway, plus she doesn't actually want to bite, she air snaps, she snarls, she barks, but she has no intention of actually fighting, all she wants is space to enjoy her walk in peace, which we are both entitled to. If you cannot call your dog back before it says hello to a leashed dog, then you need to keep it on a lead.
This thread was from ages ago. I'm not quite sure why it has resurfaced. After trying and failing with BAT (because the other dogs inevitably followed us) we have gone back to other training methods including me treating her the second she spots another dog, then jogging past while talking to her in a bright sing-song voice and treating again when she has passed without reacting (we still get other dogs following us, but generally because Whippy is paying no attention what-so-ever to them they sod off pretty quickly) and utilising the calmer more confident dogs I have access to (a recently rehomed foster and one of my Dad's lurchers) and getting them to greet the strange dogs first, which gives Whippy more confidence, because as I said, these dogs give out very clear calming signals which calms both Whippy and the excited new-comer along with extensive off lead socialising. We have made massive improvements within the last couple of weeks.
The I Need Space coats look great, though, I will keep them in mind if I ever need one for a foster/sick dog.