This brings up a good point about bus services, even at times when their are no strikes. I have observed that most of the bus accidents (and there have been some with heavy casualties in just this last week in southern China) are private or charter services rather than the official public buses. Even though the latter are not immune from dangerous drivers, it's the private enterprises that seem to have the cowboys, take shortcuts by going over capacity, etc. I have been on a LOT of intercity buses in the last 3 months, all publicly scheduled services, and have been amazed at how safe and careful the drivers have been. Every one of them. Also, private services tend to drop you in odd places, as they can't go to the public bus stations. You must be very alert and particularly if not a Chinese speaker.

So, try to ensure that your bus service is a public one--normally buying a ticket at a public bus station window ensures that. Buying on the street, or from a tout or from another business such as a hostel...may get something different. Of course in times of bus strikes, your inexpensive options may be more limited. In these cases, if a train is available even if pokey, consider hard SEAT as a safer alternative. Or if you have the funds, arrange a private car and find some like-minded travelers to share. And for ALL buses, try not to be on the road after dark, the exception being moving through big city traffic in the pre-sunrise or post-sundown period.