FWIW - Jake and all, that is not my tether requirement. That is an item we added during our formation of the GYA/US Sailing MHC Safety Recommendations, which have been a work in progress, primarily with Chuck Hawley and Randy Smyth. Jonathan Farrar encouraged the use of synthetic trapeze wires because some classes were still requiring stainless in their Class Rules for the Tybee, and stainless can not be cut with a personal knife.
We fine tuned the recommendations under Mr. Hawley's guidance.

Safety harness and tether with quick release device at user’s end, for each crewmember. (5.02.1)
If I could add attachments, I would send you Chuck's compilation. If someone would be kind enough to send me the trick for attachments via PM, then I could share the document.

This does not require constant use, but does support the ability to tether when in doubt.

This recommendation is a feature, modifiable by the owner, and the ultimate tethering system is still being developed. As boats have become faster, the design has required refining from the old Forespar straps and heavy buckles/clips we used on displacement boats.

I see no reason that a properly rigged "chicken" line could not serve the purpose. We have used those in the past, and many catamaran sailors still use them.

Just sayin' again: it is not Bert's ruling.

Respectfully,
Bert Rice