It held up nicely, after 7 miles.  It was like running on tin cans.  The Loctite Metal did release near the flexing point, but it probably wasn't worse than hot glued plastic. 

Fabrication involved a lot of drilling.  Drilling holes bigger than 1/8" in titanium must be avoided.  This process could probably be done with V cuts & grinding.  Grinding titanium causes dramatic work hardening, but it hasn't been a problem for this application.   That was all the titanium the lion kingdom can afford, for a long time.

Heat was the last remaneing problem with the laces.  The resulting sweat would dry & attack the achilles tendon.  After 11 miles in 90F, the 1/8" string solution didn't chafe anything.  They could be any tightness. The farsteners were easy to adjust.  Replaced the orange ones with black ones to make the toe plugs tighter.