Tensioning frac rig with swept back spreaders

[Brion Toss]

Hello,
I believe you are seeing two things at work here: too much overall tension for downwind/light air work; and improper relative tension, with all wires at the same tension, regardless of the length, or the actual relative load.
The first issue is about fore-and-aft mast shape, and it is easy enough to address, usually just a matter or slacking or tightening the backstay and/or runners. The second issue is a matter of tuning, and it can address the much more complex problems of lateral mast shape.
Fair leads,
Brion Toss