My own experience with this scenario was many years ago as the doorer, not the dooree, I am ashamed to say. An absent-minded moment on my part resulted in nailing a passing roadie - the noise of impact was terrific. Fortunately he was uninjured but his expensive Cannondale was pretzeled (I was also lucky that he was only mildly angry and not ballistic). My car insurance company later explained that it was my fault in that the circumstance was such that cyclist had no chance to evade the door. It would have been a different assessment if, say, my door had been open long enough for the cyclist to easily avoid but had not seen because his head was looking down instead of forward. They settled with the cyclist for a new Cannondale and several hundred dollars in return for a signed waiver of any medical claims. It was a lesson for me I've not forgotten. Whether as a parked motorist or a cyclist, I'm constantly aware of my surroundings, especially in or around a parked car on the street.