Since I was trying to give an example of two compatible classes, no, it's not apt, since their member functions have incompatible side effects.
Hm... Hypothetically, with a lot of effort you could design a dummy class (A) that implements only the members you want to investigate and where necessary returns a different dummy class (B) representing the element type. If someone ever tries to take the address of a B (you have to delete operator&() and/or get() if it's some kind of smart pointer) then you know you might be dealing with iterator invalidation.
Hm... Hypothetically, with a lot of effort you could design a dummy class (A) that implements only the members you want to investigate and where necessary returns a different dummy class (B) representing the element type. If someone ever tries to take the address of a B (you have to delete operator&() and/or get() if it's some kind of smart pointer) then you know you might be dealing with iterator invalidation.