Re: Gingivitis and foul tasting mouthwash
the chlorhex is really good at targeting the bacteria causing perio disease, but as you rightly point out it causes taste disturbances. this is because its method of action is to stick to the tissue in your mouth and release over 12 hours. this effect is accumulative aswell (ie-the more you use it, the worse your taste disturbances) and used too much it can cause reversible tooth staining. i don't think you should stop using it- use it maybe once or twice a week (like a weekly disinfectant), and a couple of hours after brushing as it is de-activated by the calcium in your toothpaste!
the post above mine is right too, listerine has been proved to be the next best thing and doesn't cause tooth staining. i read a study recently which showed 7mths of listerine use in patients with gingivitis and gum disease caused a huge decrease in plaque accumulation and disease causing bacteria.
other than that, a regular scale and polish helps too!