This question already has an answer here:
Is it possible for two networks to have the same network IP address if two different masks are used?
Take for instance the addresses
18.104.22.168/27. I'm thinking that this might be problematic. Suppose a router that connects the two networks recieves a datagram whose destiny is, for example,
22.214.171.124... How can it know where to send it? What path would the datagram follow? AFAIK, the host could be located in any of the two networks described above, so I don't see a solution if this is allowed to happen.