Horsegoer-
If he is on a cycle with the nap as an anchor, that may be just where he needs to be. That is, rather than looking at it as loosing daylight, it might be more accurate to accept the daily nap as a blessing that is preventing more serious sleep problems.

If he is taking the mucuna with the sinamet then he is to a certain extent trying to compare apples with oranges. If he is determined to try to improve things while resisting a nap then he might consider cutting the sinamet as he (slowly) increases the MP. Worth a try but if it is a case of stubborn will refusing to accept that limitations come with age regardless of PD then you have your work cut out for you. Good luck. - Rick