Like, even with a rank 3/4 surgeon for a lot of injuries it's just faster to sail back to a port to heal up. E.G. 7 days to heal even with a high-ranked surgeon - who actually just sails around and waits that out?
IMO crew injuries should either be short enough so that the injury could actually be relevantly healed (maybe balanced out with a higher medicine cost). OR, docking doesn't provide an instaheal.