Discovery operation is needed for OpenID to work.
Regarding the dumb mode, here's an excerpt from the blogpost you have pointed:
Note that by default the consumer manager works in the smart mode and will take four attempts to create an association with the openid provider. Since we have set the number of attempts to zero, the method returns only the DiscoveryInformation object and would make no association though the name of the method is "associate".
According to it, that client program does operate in dumb mode.