I can't explain Ramsey, but it does seem that the further offshore you go, the nearer 'the norm' the tide seems to be. Basically slack is 2.5 hrs after low 3 after high. It runs North either side of 'high' and south either side of low. Another strange fact, and a bit hairy if you are diving it, is the speed of tidal pickup as the North going run begins. I've seen the tide take a 2ft diameter buoy under water 7 minutes after the end of slack on a big spring. Scared the **** out of me, as I'd been in 10 minutes before that.

Golden rule - assume nothing, don't ever believe you know, and speak to everyone.