nonsense?

which part?

however your link is interesting albeit relating to a full size aircraft design- where reynolds numbers are a lot higher than the realms of models.

my point still stands that for a model which is not involved in contests where reducing induced drag helps you win, tip shape is not important. I.e. in silent flight or free flight contests you need to reduce induced drag as much as possible.

If hoerner wing tips where best then all competition silent and free flight models would use them.

As a matter of interest what's the stall like on a 60 inch span piper cub? (i've been told they can have stall vices - but you wouldn't expect that with a flat bottom section and a rectangular planform).