Umm... I guess most of the world's sailboat designers are wrong then? Mine seem to drain quite well when heeled over, must be something wrong
Mine were designed by McCurdy and Rhodes. So far they have been quite satisfactory.
Depends on where your outlets and drains are. My drains are on each side of the cockpit. The upper drain will not have any water against it when heeled unless cockpit is swamped. I have two differently configured boats. Since this is an "design" problem I mentioned them both as possibilities. However, as I mentioned, both systems are too small for serious off shore work.
Do NOT use automotive hose for below water line use unless you have the boat well insured. Use USCG below water line hose only. Available at marine stores or online.