Yes, fun.
But meaningful.
The landing gear-holding triangle controls a few things:
1. Controls the position of the landing wheels.
2. Controls in part resultant CG of the flight system, by design. And altering design masses and profiles of that triangle and its appended parts will control the resultant flight characteristics of the flight system.
3. By some pendulum action the shown triangle and its wheels controls in part resultant flight.
Such triangles and the understanding of their aerodynamic importance form roots of aerodynamic concerns.
Indeed in that same decade, we have posted photo evidence of a battened semi-flexible high aspect ratio sport-meet used hang glider that has such triangle, but cable braced and kingposted. The triangle control frame of the hang glider of that meet is situated for Whack landing gear; the Boy's book of models would suggest to big boys that wheels might help regarding some Whacks.
Indeed, the shown model does not indicate dynamic or variable-action controlling of flight. But the points above lets the fun considerations flow. Such is relevant especially since variable-push-and-pull use of such triangle in sport hang glider at official hang gliding meet in circa 1910 occurred. From the model world, it might be easy to imagine the young boys knowing about C.G. and the open opportunity of hanging a pilot below the keel to push and pull on that landing gear to effect weight-shift controls, especially since they may have been aware of Otto Lilienthal as evident in same book that indeed did feature Otto Lilienthal.
Not stretching too far. But fun and part of the research. TCF (even if the variable-push-pull dynamic is vicariously an opportunity).
Thanks for the post, Frank. It feels like you are energized from your recent adventures, maybe still ongoing.