I tried this last night with pretty good results. I was taking my 1/2 Sinemet just as I was going to bed, and only an hour or 1-1/2 hours after my last full Sinemet. This worked okay for awhile, but not so recently.
Anyway last night I held off taking the 1/2 until I started stiffening up around 2:30 - 3:00 am. This 1/2 dose helped me get back to sleep until my usual 6:30. 7:00 rise.
Thanks for sparking the idea.
John