This post is in response to Geronimo's question on the earlier post regarding foam insulation.
When I bought my DS1 last month both benches had cracks at the hull joint: the port bench at the forward corner, and the starboard at the aft corner. The cracks reached up the sides of the seats and were the result-- I am now sure-- of the boat sitting for a prolonged period of time on a poor set of bunks. The hull gradually sagged and the joints failed.
The first thing I did was fix the trailer using Phill's excellent plan for plywood full-support bunks. That actually closed the cracks up.
Then I repaired them using a fiberglass epoxy kit from Home Depot (very reasonable $$$). I went extra wide on the hull joint (4-6"). The joints are holding very well. In the process of doing this work I've discovered a few more hairline cracks on the hull-bench joints and when the season is over I plan on giving them a good lookover. The cracks may only be in the gelcoat, but I definitely think this joint takes a lot of stress-- on the trailer, and maybe some when afloat.
Hope this helps.
Wyatt