Using a hardwood strip sounds like a good idea for stapleless construction. Choose a great looking wood or one that will either contrast or blend with the cedar you use.

If you do not wish to go to the expence of purchaseing a hardwood plank to make two strips, you could use a peice of your cedar or just pine for a sacrificial shear strip...do not glue it to the next strip but just use it to hold things in place. you could even make it thicker than the actual strips to better stand up to the tape and clamps.

--eric