My old deck comes off tomorrow and the new goes back in 2 weeks after I add some wiring and repair any damage. But I'm wondering if I should fill in the old nail holes on the top edge of the joists first. Won't water wick under the new boards and collect in many of these holes, leading to potential problems?

I've heard some recommend lining all the tops of the joists with butyl tape, but my idea is cheaper and easier.

I'm wondering if not a good preventive measure to shoot a dab of polyurethane caulk into each nail hole before the new boards go down. Whole job would take 20 min. Or any reason this is a bad idea?