Hmm. See this is one reason why some people say it's not a good idea to actually give a treat for weeing.
I think part of your problem is that rather than her seeing "Toilet" as a cue for weeing, she's viewing it as a cue to come running to you for a treat. You've effectively trained "Toilet" to be a recall command 
Which is fine, but I reckon there's every chance she's cutting her wees short to come running for a treat.
If I were you, I'd drop the treating when she's tiddled. In order for a dog to associate a treat with an action, it has to occur within (at the longest) 4 seconds so I really doubt she's linking wee=treat.
I'd go out with her, put a NEW word to it and not treat.
What can also happen if you treat for weeing is that if the dog DOES associate the treat with weeing, he will associate the ACTION with the treat rather than the location - so it isn't unheard of for dogs to squat down and wee on the carpet RIGHT IN FRONT OF THE OWNER, looking up hopefully in expectation of a treat! And really, when you think about it, it's a hell of a stretch to expect them to realise that it's the location you're treating rather than the action.
It's the same principle that dictates you should NEVER punish a dog for weeing in the wrong place; they can become fearful of eliminating in front of you AT ALL (again, assuming you're telling them off for weeing, not for the location), and you're then in danger of having a dog who hides behind curtains/under tables to wee/poo.
No idea whether she's got SA - impossible to say over the net. If they're full wees though, and she's not damaging anything, I'd lay money on it just being down to her not being totally empty when she's left.