Things that I have heard recently:
In a meeting Lester brought up protection schemes, and gave an example of a specific play. Center heads to the line and calls out who the Mike LB is, and the blocking scheme is dictated. Lester tells the other coaches you guys have been doing that for 20 years. Everyone knows what you are doing before the ball is snapped. We are going to do some different things on blocking schemes. Someone asks Lester if Kirk is onboard, and he gives the same pitch to Kirk, who agrees. Moral of that story, is not necessarily Kirk has been headstrong, but has anyone been willing to challenge the status quo?
Second item, expect more motion right from when the huddle is broken. Make the defense constantly react to you.
Third, Phil Parker commented about the number of points scored in practice. On this I couldn't clarify if they meant the Spring game, or not, but Parker mentioned 6 TDs were scored, and 2 had been the most in as long as he could remember.
Fourth, he is higher on the WR talent and the o-line than fans are. That could be self serving and inspirational, but there is offensive talent in his eyes.
The opinion I received is Lester is energetic and vocal, and not here for the status quo. One thing I heard last year was that Brian did a lot of walk throughs in practice. Expect more energy and tempo in practice, and on the field.