We do a lot of work in leaded steel and cold rolled and hot rolled C1018 and on the production stuff always use flood coolant with modest speeds and fairly good feeds.
Doing prototypes and fixtures when I am working with one offs and can take the time to get conditions correct I often machine dry with an air blast sometimes at very aggressive speeds and feeds.
The main reason I have never changed over to dry machining for our production stuff, even though it could possibly boost productivity, is that if something does go a bit haywire you can burn out a tool very quickly and because our production stuff runs on mini-pallet systems with the machines un-attended you finish up wiping out a whole lot of tools. Sometimes it is better to be conservative.
An open mind is a virtue...so long as all the common sense has not leaked out.