This is true.
The one problem I had after doing so many chins (besides a bigger back) was a muscle imblance from not doing enough rows and some shoulder pain later down the road.
However, I did a lot of rows, snatches, cleans and deadlifts to help counteract all the chinning, and I also eased up on the chin work.
But I had done all this chinning throughout an entire year, as my back was a weak spot. But now, my back is one of my best bodyparts. I have backed off (no pun intended) on back work and only do chins one day and rows another.
If you do it as listed (a few reps, throughout the day, each day), then you will get stronger and add some size. just don't forget to do some rowing and other stuff during your regular workouts.
If you feel like you're getting burned out or creating an imbalance, back off! If trying to focus on your chins, this method works to increase your strength and the amount of reps you'll be able to do.