I forget to update: I checked the table out yesterday after I got home. No water puddled on top. Table was a bit dusty but I didn't see evidence of road grime/water spray. And that was with 150 miles of rain at 60mph.
As of right now, I won't be making any changes.
I guess, as I think about it - the underbelly itself doesn't get covered with road spray. And the rails are right beside the table itself, literally covering the entire edge of the table. I guess airflow under the TT is such that it never really sucks up on to the table.
