I'm glad to hear that he found the formula effective. I've answered your questions inline below:
1. 1-3 months at full dose would be considered a therapeutic dosage. For fertility, where we most often use this formula, generally they are on for 3 months. If there continue to be issues, it would 1 month off and then another 1-3 months.
2. Generally with herbs it is good to take a break from time to time. I would recommend in this case to take for a complete month and then take at least 1-2 weeks off to see if the issue returns or not. Then repeat in that order until the herbs are no longer necessary. If the herbs remain necessary then acupuncture or other therapies would be required.
3. The goal is certainly to create a permanent change in the condition as opposed to managing the symptoms.
4. Not with this formula, this is a pretty standard and safe formula for the conditions listed.
5. See #2 above. Yes, if the herbs alone are not effective and/or not leading to a permanent resolution.
6. Yes, herbs, particularly in patent formulas like you gui wan, are in very low doses. They should be taken at full dosage for a period of time regardless even when they are effective. After a period of time many formulas can be taken symptomatically or a day or so at a time for effect, but initially they should be taken on a consistent basis.