Thanks for your comments.
To draw a graph of your levodopa equivalent plasma levels taking into account the size and timing of your dose(s) you can use:
Parkinson's Disease Measurement: PwP, surveys, trials, analysis
I've been given the "too onerous" line by medics too. I say that you must have a very mild form of the disease for it to be too much effort to take an extra dose if that is more optimal. I think a better argument is one of compliance: the more doses you have, the higher the chance of missing one (but the smaller the consequences).
Rather than having to halve and quarter the pills, why not have a range of pills with smaller doses?
I've tried dissolving Stalevo in Vitamin C. That allows you to draw off whatever dose you want.
John