How would principals/teachers know if and how much the sample lesson transfers knowledge to students? It seems like this would filter out disasters, but can it do more than that?
That's when you look at other factors like past performance, including (but certainly not limited to) performance on his / her pupils' standardized tests. Like any other hiring process, it's not always perfect, but you also learn along the way which characteristics make for great teachers (responding to feedback, ability to engage with students, timeliness, etc.).
