Tim Lackey, #381, GLISSANDO
My opinion of the tuning tips on the MIR is that those were written a long time ago when racing Tritons was much more common. Tuning the mast like it describes in the article will set things up very tightly--unnecessarily tight, in my opinion, for most types of sailing. There's no need to overstress things. Tight enough is tight enough. Only some actual sailing and use of your particular boat will show you how much. For racing, I think that the basic premise of those tuning tips seems sound.
Tuning a rig is not brain surgery, and generic tips rarely work perfectly from boat to boat because of the inevitable difference between their setups. Your only goal in initially setting up the mast is to get it straight and standing on its own--very simple. More precise tuning will come later. Remember, the main goal with all rig tuning is to keep the mast straight and in column under a variety of conditions. Usually some minor tweaking is necessary after the mast is first stepped, but this has to be done "on the go", and I have never seen pre-determined setup guidelines work particularlly well on all boats.
As far as the jumper tension, I have found that something a bit tighter than hand tight (when the mast is down) is sufficient. The idea behind the recommendations of the MIR article is that you tighten the jumpers so much that, when you then tighten the backstay, you will have drum-tight headstay and masthead--again, this seems unnecessarily tight for most sailing. The key when tensioning the jumpers with the mast down is to tension both sides equally, and to ensure that the jumpers remain in their true plane up and down and side to side. Tighter jumpers mean you will be able to get a tighter headstay with less sag. But you don't have to go to an extreme to get this, either. Wire rigging will stretch over time after initial setup, so adjustments down the road may be necessary. A nice upgrade is installing turnbuckles on the jumper stays where they attach above the lower spreaders, so that you can more easily adjust their tension later. Still, I have never changed the initial tension I put on the jumpers each year when the mast is unstepped.
Remember how all the gear and everything else on #100 is all warped, tweaked, and torqued out of shape? Overstressing the rigging is why. Approach with caution, and go for looser than you think. You can always tighten things up as you go along, but you need to see how things set up on your own boat first.