Dick,
Your instincts are absolutely correct about including the canard area. In fact, since the canard must (for stability sake) be considerably higher in "loading" than the main wing, it is carrying more than its share (per sq. in) of the weight of the plane. If you figure a 30-40 percent higher wing loading on the canard, a perfectly logical assumption, then you have the canard running at upwards of 32 oz/ft, a far cry from the 26 you expected. This translates directly into minimum flight speed.
In terms of performance, the wing loading on the canard is the main issue, not the loading on the main wing.
A canard IS a kind of biplane and anybody who tells you otherwise is misinformed.
Allan