In my experience, the CxO's would likely chuckle if they found out (AND all your actual work is being done 100%). Middle management would likely not be very happy.

I used to spend at least half my day wandering around our campus because I could get everything done in 2 hours and would typically do another 2 hours because that would double my output. I couldn't get a 400% raise and I was satisfied with the amount of work I did, management wouldn't fire me because I was providing them with an awesome deal, etc.

I didn't tell them I did not work half the day. There's a lot of unspoken bullshit in the corporate would, normally it works against employees and I think it's okay for it to work for you sometimes, too.