The problem is that the SK_REF skeleton value returned from the scoop melted attribute access has a melted code flag encoded within, the generated code always checks == SK_REF when it should do a mask with SK_HEAD before doing the check.  The type panic is because for some reason the code always generates a boxing alternative path even though this cannot happen in this scenario, when the SK_REF check fails it tries to box the value which results in the type panic.