Other than me and you @belltown, there probably are somewhere between 3 and 5 other people outside RokuCo that know and care about the difference between "roArray" and "roList". And i still don't know the reason to differentiate between these two - if Lua can make-do with only 1 type ("table") for both lists/arrays and hash-dictionaries - why can't B/S settle on only [ ] and { }? Perhaps for h*st*rical reasons but a good number of APIs return roList instead of roArray.
So from a pragmatic point of view, un-handling of roList is a shortfall of formatJSON - even if by documents it could not be "convicted" of a bug. roList looks like a duck, quacks like a duck... it should formatJSON as a duck.
Regarding the partial documentation as "Formats an Associative Array as a JSON string" - that's a leftover from two years ago when formatJSON() was accepting only { } at top level and was crashing the player with cyclic structures, cue
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