If you do a search on vinegar, you will find a few posts where it has been discussed.
Here is one to start with -> http://forum.beemaster.com/index.php?topic=7326.45
I think you will come to the same frustrating conclusions that I did.
1. There is no real data available, only people that love it and swear by it. These are the same folks that have spend $600. If I spent that much I would lean towards it working too, right?
2. If there is merit to acetic acid (which I have no bias either way to), then why does it take a $600 piece of equipment to apply it, when the other acids can be applied with methods that cost nearly nothing. I've tried to understand the application method to see if I could build one, all those that tout it are very tight lipped......