Example:
mob
one
set default_verb_category = "One"
verb
Hello()
World()
two
set default_verb_category = "Two"
verb
Hello2()
World2()
Instead of having to specify set category = "" for each individual verb.
Edit-
Of course, if set category is specified, it will overrule the default_verb_category for that one verb.
This could also replace the current client / default_verb_category which only specifies the default category for any verb which is assigned to them.