I agree Chip ... pick some of your clients and ask them how they would prefer to deal with the issue.
The other side of it is to establish a test for the result. You will need to identify some key metrics, then measure them before and after the change. This will tell you if the change is affecting your sales negatively enough to try another tack.
As a PM, 80% of my job (or more) is communications. I absolutely have to charge for time spent in communications. Although like you, I try to seperate the communications into done for me (no charge) and done for them (charge) buckets.
Glen Ford, PMP
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