Depends what kind of meditation. For the practice the author is talking about (vipassana) It became much more enjoyable and that didn't decrease the benefits I got. It moved beyond working through letting go of patterning, into understanding the nature of my human-ness and being able to work with that better(insight). And... I'm certainly not done with patterning haha....

I do think it starts to S curve on the benefits received against time committed. When you get to that point though, your overall life will be more than likely at a fantastic point.