What is best is that children learn as much as possible, as well as possible in the time they have available in the lesson. That could be through lots of teacher talk or not a lot of teacher talk.
In my continuing attempts to balance the somewhat one sided view from some bloggers about teacher talk, I want to make the following point.
if one judges a lesson to have less learning than one would expect one of the reasons for this could be too much teacher talk. It is rather obvious that in some lessons teachers will not have recognised that they have said enough. The students have got it! You don’t need to go on any more! So there will clearly be Ofsted reports and other observations that can have identified too much teacher talk as detrimental to learning. Too much talk can waste time, as much as anything else that does not drive learning forward.
Just did not want you to get the idea that more talk was better.
Nor do I want you to get the idea that less talk is better.