rather be frank with people in giving feedback. What I love best about his comments is the open acknowledgement that he doesn't always do it as well as he'd like and that he knows some people are going to walk away with a bad impression but it's still worth it to him. That is leadership and it is also service because he's right, it does take a lot more work. One thing he didn't touch on was how to get those kinds of benefits from others who may not share his philosophy.
Mark calls out yes-men as a problem and, accurately, ascribes much of this to laziness. So if you're a leader and you want real feedback, dig a deeper when people tell you things even when they approve. If they say they think something's great ask them why, get them to explain themselves. Don't go light on this either, if they don't have to pause a little and think you probably haven't pressed quite enough yet. Much like giving real feedback, doing this will make people uncomfortable and they may well not like you as much. Yet you will get two benefits, good feedback and an increased likelihood that that person will be a better adviser in the future.
I've had experience with this when designing a safety program. When I first presented it to my group everyone went along with how great the ideas were. That was kind of ridiculous since, of all of them, I had the least direct exposure to the work environment. So I asked them what they thought was good about it. The room got very quiet. I let the quiet build for a while and then expressed my confidence in their expertise and knowledge. Then I waited again and first one and then another idea came out of the group. At first it was just an affirmation of the good things about the plan but as they saw I wasn't going to shut them down they got more bold and began giving me areas where it wouldn't work and what needed to change. It was glorious, we actually got work done in a meeting that had threatened to be a cheerleading session. And the next meeting? I didn't have to work nearly as hard to get the ideas flowing.
I highly recommend following Mark's advice to not be a yes-man but if you go this road do it well, make the effort to become good at it and not just a jerk. But it's also important that you get that kind of feedback yourself or your own development and work quality will suffer. So when people give you praise or agree with you, ask them why. Explore their thinking and if you discover they don't have any then give them honest feedback about that.