Not sure I understand your intention. Are you planning on mounting the lights on the underside of the bottom of the trees facing down so that the light reflects off the plastic squares in effect creating an up-lighting\wash effect on the trees?
Also I have a question, if you take dumb strings and cut them up, add an ic for every segment, they are now not so dumb, but yet they are not truly smart either. So what are you going to call these? How about semi-smart strips (sss). Just a rookie's feeble mind meandering for what it is worth.
Oh, also dawned on me that the other benefit besides the ones mention previously about the setup, is that it will sure help keep the channel count down, yet give you the flexability you need to create chases on an arch or eves.
Keep up the great ideas and hard work. looking forward to seeing the video as well.