I've complained about On Demand being buried in the menu settings quite a few times, but I've never seen a suggestion to create a one touch button on a Harmony to load On Demand without going through the menus. I was using the remote in the D* app on my phone today and noticed that there was an On Demand button.
I got the Google out on my computer and decided to look into adding the same button to my Harmony, and I learned that entering channel 1000 into my remote would take me straight to the On Demand menu. I added a simple sequence to my D* activity that punches in channel 1000 and assigned it to the long press on my DVR button.
You do have to watch channel 1000 fly by on the info overlay, but it's quick, and even on my old dog HR23 the On Demand menu loads much faster this way than when you wade through the menus to do it.
Watch Now has made On Demand a valuable feature for me, and now with one button access to it I'm a very happy camper right about now.