Pleased to see that the platform pedals pictured in this thread are, indeed, platform pedals. (Even if they don't look or perform like the Lyotard Marcel Berthet platforms I used a long time ago. They were designed to work with toe clips.)
What do I do on my 'bent with SPD clipless pedals that I couldn't do with BMX-style platform pedals? When getting ready to take off from a dead stop, I can put my right foot on the pedal anywhere in the rotation and move the crankarm up, down, or all around to get to the sweet spot for a takeoff.