Towing your boat behing a houseboat with dripless shaft seal

This has been brought up in a few different forums, wanted to get feedback from WW members. It seems there are a lot of different opinions on this...

If you tow your boat behind a houseboat with a dripless shaft seal will damage occur to the seal from lack of water being introduced into the seal unit. The prop will be spinning, and there might be some water forced into the scupper, but is it enough to cool the shaft and not damage the seal? how fast is th prop actually spinning at houseboat cruising speed?

I do this when I am on Lake Shasta, and wanted to find out if I am taking a chance of the seal being damaged. My last boat had a dripless shaft seal and failed prematurely at 230 hours, I am now wondering if this was the cause of the failure.

Thanks for any feedback...