I think that Smartie, the OP, has been given an unnecessarily rough ride because of his candid comments about obtaining a complimentary release letter. The truth is that it is a common occurrence in Chinese culture to offer such niceties to one's boss in order to gain his favor. I worked in one school in which the foreign teachers' relationship with their department liaison was so tenuous and volatile that we were truly at wits' end. A Chinese friend who is neither inexperienced nor naive suggested that we present the liaison with a cash gift, treat him to dinner, or present him with a simple bottle of baiju to sweeten him up. We ruled out the cash immediately (our cultural values at play). Dinner was voted out because we didn't think he'd accept, but if he did we were unsure just how well the evening would turn out. We settled on the baiju. Since none of us liked the stuff, and none of us had much experience with it, we gave my friend 100 rmb to buy a good bottle of baiju. (Yes, I know: "good" and "baiju" are oxymorons). I don't remember how much it cost, but I do remember getting a LOT of change back.

At the end of the term, when we turned in our grade books and all of our textbooks, we presented him with the bottle of turpentine --- I mean baiju--- and the guy's demeanor changed drastically. My Chinese friend was right. A little grease goes a long way. The next term, our liaison went to bat for us to negotiate with the department for us to have more reasonable schedules and more reasonable timetables for handing in required paperwork. At the time, there were no required Letters of Release, so I can't say whether our gift would have changed the outcome of any evaluation issued in the form of a letter of release or a letter of recommendation (which is not the same as a letter of release. Now, the letter of release is mandatory on the part of the FAO. The letter of recommendation is something that is voluntary and may be issued at the discretion of the dean of the foreign languages department or the FAO).

Re: becoming a better teacher in order to obtain a good word from an employer. In a rational world, it is a reasonable assumption that doing a good job would prompt an employer to communicate good things about a good employee. Anyone who works in the real world for any length of time learns that doing one's job well does not always earn the respect and admiration of his employer. In a previous China gig, I worked with two wholly incompetent foreign teachers. One professed to have ten years experience in EFL and BA in English. The other had about four years experience in China and professed to have a Ph.D of some sort. Neither demonstrated any class room ability. One teacher's classes went on strike and refused to respond to him after mid-term; the other teacher's students complained bitterly to me about her incompetence and iron-fist approach to "teaching" as well as using her class room as a pulpit to trash the school, her students, and her foreign colleagues. (I know about their complaints because we shared a couple of groups of students. I had to hear their complaints, though I instructed them not to complain to me but to their group leader). At the end of the term, the ten-year veteran was given a letter of release with no negative remarks. The Ph.D retained her job and her exorbitant salary.

How did they do it? Each spent a lot of time in the FAO's office schmoozing the waiban. It didn't matter one bit to the waiban that they were incompetent, and the foreign teachers didn't care that their students hated them or that the foreign languages department viewed them as bad teachers. The foreign teachers knew that the FAO held the power, so that's where they expended their energies.

These are just a few of the realities of teaching in China. For some strange reason, frauds and incompetent teachers demonstrate remarkable ability to maintain employment in China not because of their teaching skills but for their political acumen. This occurs not only in China TEFL but elsewhere in the world and in other areas of employment.