I have just one HC officers sword from 1869. My own thoughts on why a half basket would be access. A half basket goes back earlier, just like half heart counterguards.
The evolution of the swords are covered by lettered authors, such as Dellar. On Facebook, Steve Goodyear has done a lot of the variety of evolution.
https://www.facebook.com/groups/1402...0008637461346/
Another reason for a half basket is wear
Cheers
GC