Visa Man, thank you for the update and I bet many others will be thankful as well. Many, inclusive me, that have been in China for a while know how illegal it is to work on an L, but imagine that you are changing an employer. It's pretty difficult to extend an RP that is valid until the last day of your employment contract and with an employer you wish to leave. That's was in my case when I had to work on my last day of RP validity as my employer provided me with a work visa until the last day of our contractual agreement only. My last month on that job was busy and so I had little time to search for new opportunities. I bet many others may get into similar situations where they convert their work visas into one month L visas and when they assume the new position there's usually an overlap there. Otherwise, if we want to change employers, we'll have to get out of the country first. Yes, I guess that's what the Chinese authorities are hoping for as they're playing into the cards of local employers...either you are loyal or get out! Another issue is the one that you've mentioned with foreigners arriving on Ls and then seeking and/or assuming job positions in China. In this case, my view is that the local authorities are to reduce the competetive foreign teachers' job market. Ironically, some employers want to see us before they hire us.
I'd say
Cheers and beers to our successful exit rather than arrival
Some people think it is OK to arrive in China with an L ( tourist visa ), and teach until it is replaced by a Z(work visa ), that being eventually accompanied by an RP ( Residence Permit )
Here is the truth: It is illegal to arrive in China on a tourist visa, and then start working.: a person caught teaching with a tourist visa on his/her first day of teaching is guilty of an offence, just as someone caught when he has been doing so for ten years! Chinese immigration won't exonerate illegality!
If caught working with an L visa you will be fined, prosecuted, even if that L visa was going to be replaced by a Z(work visa), before it's one month validity had expired. Incedentally, you have a greater chance of being caught working with an L visa for a private training centre than for a university. This is just what I have learned from personal experience.
That said, many universities will not employ FT's with an L visa. Anyway, working with an L is illegal, no iffs, no buts!