I would only try this on purpose in a Flanders. You could probably get away with it in the Flanders style. But don't expect everybody to love it as much as you might.
That said, I have successfully used a splash of vinegar to acidify my MASH a couple times, and it works, and with no detrimental effects.
In any case, you just don't want to overdo it... and it would be VERY easy to overdo it. Once you've added too much... well I hope you have a need for several gallons of salad dressing!!