I've had the same problem with The President, not The actual president...anyhow, lots of growth but no flowers.
Mine is not down to hunger, but it is a bit of a rescue plant, having been forgotten about and newly discovered last year. Since Clematis group two flower May/June on last year's growth and flower late summer on this year's growth, I am assuming that last year's growth was more a question of re-establishing itself, as opposed to thinking about forming buds. I don't know why a plant would decide that, but is it possible that your 2yr old was too busy making roots and things before getting into the glamour business?
Just a thought. Patience and BobTheGardener's advice should see you through