Just a thought on setting dolphin striker tension.

Let's say have nothing better to do one day and decide to put your boat in sailing trim on the beach for the purpose of checking the toe of your boards. My boat has pivoting center boards and I sail with them both down for the most part so I need to be sure they don't toe out. Very slow.
Most boats when sheeted hard will pull the bows together
so that shouldn't be a problem. If you have all the slop out of the boards and there are toed still toed out what are you going to do? Tightening the striker bends the beam and the effect is to pull the hulls closer together at the main beam which toes the boards in.

This was very effective on the TheMightyHobie18 with it's curved main beam.

So The proper tension is what ever it takes to get this part of the boat tuned (albeit) fine tuned.

And loosen the rig before trying to make any adjustments.

Something else to play with.