Closes #147: Won't crash, won't max performance

Unfortunately the delambdafy approach is fundamentally incompatible with
the miniboxed function representation. While miniboxing stores functions
as @miniboxed-annotated classes, delambdafy stores them as methods. It
may be possible to bridge the gap efficiently, this is outside the scope
of this bug and is a difficult project on its own.
Separated test for #147, since it only affect 2.11

also fixed an inverted condition and a test comparison issue.