The arrow analogy is actually not a good analogy at all. If you are stringing at 60 pounds and you actually were able to hold 100% of the 60 lbs, you would absolutely hate the stringbed and have to cut it out. Some people are still underestimating how much lower actual, dynamic tension is to reference "pull" tension. You actually lose about 20-25 lbs from reference, so 60 lbs pull tension will be slightly under 40. You would never be able to play with a stringbed that had an actual tension of 60 lbs, it would be a brick wall. It is just much easier to use the "pull" tension since every string machine and stringer loses a different amount of tension each time they string. As some others have suggested, the best thing is to try and stay consistent and when you switch stringers you will need to adjust a little. For instance, constant pull machines will produce a stiffer stringbed at the same reference tension, and those stringers that use flying clamps will lose some tension too.
(2) Dunlop Aerogel 200 (~345 g)- Genesis Typhoon (Gray) Full Bed (55/56.5)