Will the blade angle of a constant speed propeller be at its least angle (fine pitch) during full throttle and prop full?
Prop full forward means fine pitch, so when the throttle is pushed full open the engine can spool up to its maximum rated RPM and thereby develop maximum power for takeoff. The fine pitch stop is set so as to prevent the engine from overspeeding at full throttle conditions.
With the throttle still wide open, deepening the pitch angle (pulling back on the prop control) will increase the torque load on the engine and cause it to slow down.
With the engine thus slowed down to a lower RPM setting and the throttle still wide open, pulling back on the throttle will cause the prop governor mechanism to decrease the prop pitch, so as to automatically maintain that RPM setting.