I've found a couple of deck boards on which the polysulfide caulk has pulled away from the board on one side, leaving a 1/16" gap.  Am I going to have to remove the caulk there before reforming the seam, or can I just gun it into the crack?  I'm assuming the teak deck boards are all separate boards and the cracks will probably go all the way to the underlying plywood surface.

Thanks Gary.  That's very useful to know, and somewhat consoling that the thorough hosing everything got this afternoon won't have reached any plywood underlayment (marine ply or not).  I think I'll just tape off the boards on either side of the existing caulk, clean out anything loose, maybe widen the gap a bit, especially at the ends, and fill it with fresh black polysulfide. No point taking chances.