The StaMasters you have are more than 'beefy' enough.
Very high rig tension may or may not be the fastest setup for your Day Sailer when racing. I am very competitive with Dave (4 NAC's each) and use a much looser set up.
If you want the tighter set up, Dave does not get the tension by forcing the turnbuckles or adjusters tighter. He sets up the shrouds where he wants them for the mast rake, and then uses the jib halyard and the trailer winch to pull the rig tight. When the jib halyard takes the tension of the rig to tighter than he wants, he then attaches the forestay to the bow plate. The adjuster is already set where he needs it. If he wants it tighter, he relieves the tension with the jib hayard/winch, adjusts the forestay fitting and then reattaches the forestay, releases the winch/halyard and remeasures the tension with the Loos guage. The adjuster is never adjusted under tension.
There are many traps when copying our set ups that need to be kept in mind when setting up a DS. Rig tension is important, but needs to be customized to each teams specifics. Crew weight, Mast brand, Sailmaker, Spreader lengths, Spreader angles (fixed or swinging), sailing style and mainsheet systems(mid-boom or Vang-sheeting), can all change what will be fastest for you.
Dave has an old Proctor E section. Heavier and stiffer than my bendier Ballanger mast. His high tension is to get more pre-bend than I need. He uses North Sails, I use Jotz. My sails are more forgiving of different tensions and mast types. My first major wins were with an old stock untapered Alspar factory mast (keel stepped) with free swinging spreaders. My mast is also about 3" shorter than the maximum allowed, so measurements from my boat may cause your boat to have a bad case of the slows.
For adjusters on my boat I have the Johnson lifeline adjusters on 3/32" shrouds and forestay. And I use the original jack screw at the bottom of the mast to tension it each day. (Dave and I both loosen our rigs each day after sailing). I dont use any kind of guage, just tighten and 'twing' the shroud to get a 'note' that seems good for the days conditions. If you go my profile and click on "Personel Gallery" you can find a picture of that adjuster.
Loos Guages can also confuse. I was recently crewing on a Thistle, and when studying the Thistle website for tuning tips for my skipper, I found that when tension numbers are given, they also state if the Loos guage is the older or new version of the same model. Apparantly Loos changed the design and the numbers are very different from the old to the new. I dont know which Dave uses. I dont even have a guage and have never used one.
I am not trying to confuse or discourage anyone. Its very difficult to exacty copy anyones set up in the DS. We have too many variables, boat vintage/manufacturer, mast type and size, CB pivot placement, and crew sizes, for the numbers on one boat to be anymore than a starting point for another.
Hope this helps. Sail and tweak and sail somemore. Thats half the fun in our class. Lots of room for individualizing our boats. Somehow, we still end up with a large variety of boat-mast-sail types at the front of the fleet.
Most important HAVE FUN. We did last summer, didnt we Nate?
phill