If your dog was off lead YABU.
Quite right, Booboostwo. I'd only done what I thought best in these particular circumstances, and of course with my dogs being off the lead the other owner wasn't to know that I was worried, and I'd not looked at it from that perspective.
It all transpired in a funny way, as the dog wasn't coming from the other direction, it was in a separate section off to the side where there are some caravans shielded by trees but not blocked off. I'd walked past the owner previously at a distance of about 20m and she called out a name - probably a child, I thought, and thought no more of it. A few minutes later, a dog emerged out of the trees, well over 100m from the owner and no more than 20m or so from us, and made a beeline for my dogs. I figured it was too late for the owner to catch up so best to try to minimise any stress by leaving the dogs off the lead. I then called out to the owner twice asking her to please come and collect her dog as I was worried, and then she walked over. So, I can quite see why she would think I was being unreasonable, as would you. If I'd seen the dog coming with its owner, I'd have put mine on the lead as I normally do.
It don't buy it as well that you're afraid of the other dog attacking yours. You've already acknowledged that your fear is that your male dog will attack another male dog interacting with your female.
The normal, appropriate interaction of sniffing both ends appears to trigger your dog becoming "hugely aggressive". Sounds to me like you were taking quite a risk having the male off lead.
I don't get it how owners who have aggressive dogs think that their little Hannibal Lecters are not to blame for their own aggressive actions. Keep your dog on lead, and if that isn't enough, muzzle him when other dogs are around.
Okay, I appreciate you posted this before I could clarify why mine was off the lead. I do think though, that you're misrepresenting me a little, and that's a shame as I really am on this forum to get a decent idea of how to deal with this situation rather than just looking for people to agree with me.
I think you've somewhat misquoted me with the "massively aggressive" thing - I don't mean that he is snarling and snapping and straining to get at them. He growls on occasion when an unrestrained male dog is taking serious interest in my female dog. He doesn't snarl, he doesn't snap and he has never in his life attacked another dog, and when he has been attacked he has cowered and not reacted. And yes, I am scared that one day the growling will turn into more as, unlike all these people who merrily call out, oh don't worry, my dog's friendly!, I appreciate he is an animal and no amount of training can take certain basic instincts out of him or any other dog.
it is pretty frustrating to have on lead walkers, with sensitive or aggressive dogs walking in high dog traffic areas where everyone else is offlead
I absolutely agree, which I why I don't ever take my dogs to high-traffic areas such as the lake. The other two dogs we met on the walk this morning were called to heel as quickly as mine were before we crossed paths, and then let off again. I do get your point though, and I wouldn't want to bother other owners and dogs if there was a general off-lead rule and I was spoiling it. I felt quite the same before I got my second dog and my Retriever was 100% friendly with every dog he came across.