Yes there are other ways
Hi There, I know of the guage they speak of and they are very handy, but there are other ways to tune your standing rigging. To try and describe to you the procedure I use as my rigging is new is a simple procedure but for rigging that is used or has seen some use may be better answered by someone other than me. On my Mark II I make sure my mast is in as perfect alingment as I can by sighting up the mast from the deck or if you have a tall building near by to sight with the edge of the wall closest to my mast it works as well. As far as how tight each of the stays are, my check is keeping equal the turns on the turnbuckles themselves to create a secure rig. If I were to have the sails fill with air from the port side then I would want to see the starboard stays go loose so the mast and spreaders are allowed to flex. If the rigging is so tight that the other side cannot flex at all or go loose then you will definitely be causing some damage to your rigging and possibly the mast and chainplates, turnbuckles etc, this has a rippling effect here. I have seen some stays part because of being overstressed, by trying to make them too tight. I hope I haven't confused you here. Happy Rigging Dave
