songfellow,
your're certainly helping the cause.
on the flip side, one can ask, are there too many "minor" pd trials which diverts volunteers/$$$/neuologists/researchers from the more important trials?

not really going to make an issue about this except to say this is more than just not having enough volunteers imho. like you said, it's not easy just getting back and forth for dr. visits and/or treatments.

another issue not mentioned in that video is the large number of phase 2 trials that have failed after stellar phase1 results which might deter volunteers, especially with sham surgery involved and the GDNF trials? might discourage a few people. plus with dbs, i imagine some patients get that, thinking it will hold them over until the "cure".

do they have enough candidates for gene, biomarker and neuroprotection studies? dunno.
i volunteered for a phase3 dopamine agonist trial back in 2004 - the trial was cancelled after 6 months- and a genetic analysis and am currently volunteering for another trial.
the agonist trial was very inconvenient as the neuro was on temporary contract and we'd have to sometimes wait over an hr. for him to fit us in with his normal patient schedule.