Here is a sensei after my own heart! Kondo sensei demonstrates how to do do-uchi correctly to his university-aged students. This is part of a series of new videos from Kendo Nippon magazine where Kondo sensei examines the relationship between cutting with a sword using Kendo techniques, and striking with the shinai. It's a very interesting series. He even does hiki-waza effectively with a real sword! (Against the makiwara of course, not a person!).
First he demonstrates correct technique with a shinken and cuts the makiwara using a fairly conventional do technique. Then he asks his students to demonstrate their technique. They do the current fashionable style of dropping the kensen to the floor straight after hitting the do (see video below for a good-bad example!). Which is SO WRONG!
Kondo sensei then schools them on how to stop this bad technique, in light of what he has just shown them with the way a real sword cuts. Hooray! If there's something I hate, it's seeing otherwise really skillful kenshi doing do this way. It's like a virus... :D
Don't do it like the sensei in this video at 5:29!