RainmanTrail
Straight Flush
There still is absolutely nothing more to this than "Garrett thinks that nobody would ever make that call without knowing his cards."
You say it like it's nothing though. But it is very much true that nobody makes that call without knowing their opponents cards. If you think this is just what donkeys do sometimes, then you don't know how donkeys play. Nobody makes this call. Nobody. Ever. Not without information. Unless they simply just have no idea whatsoever about how to play poker. Robbi might be new to poker, but she isn't new enough.