I don't think advocating hand sharpening is necessarily good. Take your blades to a pro and get them sharpened.
It's not necessarily good, nor is it necessarily bad. It's a choice.
I ran some metal removal experiments a while back with the Pro-Filer skate sharpener. It removes metal very slowly. Being curious, I measured how much metal is removed from the hollow and from the edges in a 2-hour marathon. After this extended sharpening session, I measured 0.004" removed from the hollow- which is about the thickness of a human hair. Routine sharpening to freshen the edges removes about 1/4 of that.
At the same time I ran my experiment, Wm Letendre in Boston measured how much was removed by a professional sharpening done by a respected shop. He measured 0.005" metal removed in the few minutes required to sharpen his blades. With a heavy hand, less experienced operators can easily remove much more and ruin a blade. That happened to me in the 70s when the first sharpening of new blades removed ALL the rocker. I know that I'm not alone with such horror stories.
I can see your point if you live in a large metro area close to a respected sharpener. If that were the case, I wouldn't waste my time sharpening my own blades. However I live 75 miles from a good sharpener in Columbus, OH, and unfortunately his hours coincide with my own working hours. It's next to impossible for me to see him.
I'd sum up the advantages and disadvantages of hand sharpening as:
Advantages:
No need to travel to find a sharpener with a good reputation.
Slow metal removal rate means very little rocker change over time - won't substantially change the rocker even after years of skating/sharpening.
Once the sharpening kit is purchased, no further costs are involved.
Disadvantages:
Takes time to do. I allow a bit under an hour to tape blades, sharpen, and clean up.
Messy if you use oil. Water will be less messy. I use oil and wear latex gloves to minimize the effect on skin.
Can't do parabolics. May have trouble with other unusual configurations too.
It's best suited for the mechanically inclined and requires patience. (I'm a trained engineer and avid DIYer, so I find it a relaxing task)
I just wanted to add my own viewpoint driven by my own experiences. To me, it's just about the only option available. Our university rink is run by college students, with only current students serving as coaches (by university decree). That also includes counter help, and skate sharpeners too - they're all college students with unknown experience. I've heard some very loud yelling in the lobby by people holding freshly "sharpened" skates, and the regulars all avoid their service.