From what I've seen in clinical collaborators in Life Sciences, they're usually driven by pretty selfish incentives - publications, conferences, money, a way to push someone's pet theory if they happen to have one. They have major jobs, with patients and hierarchical games aside from R&D, and rarely care about research progress as such. (And research is mostly low quality, with obscure clinical perspectives). They don't need to actively obstruct, but they have enough reasons not to care.