A logical argument Walter and I certainly wouldn't disagree with any of that. Holding the chuck is a habit for me I suppose which goes back 30 years or more and very correct to be cautious with advice given to the inexperienced, 'cos if you don't know - you don't know!
I think a minimum 7mm dia drill bit snapping would be a very rare occurrence however and would have to be caused by serious carelessness or a faulty drill bit. As a builder who drills thousands of holes on site and has severely abused, twisted and levered bits whilst doing so, I've never managed to snap a bit of that size.
