It's an interesting way to do it, yes.
I think what's missing here is a quick explanation as to why this may be necessary.
A lot of people swear on 8-bit mode processing only. I process everything in 16-bit mode, and when there are some very problematic contrast problems, in 32-bit mode, so that there's a lesser chance for clipping values.
One way is not the only way. If you think that plain desaturation is enough, then that works for you. For some people, the extra steps are done for a reason that they feel is compelling enough to do in order to keep the detail, feel, whatever it is.
I use the Lab mode when doing some contrast changes, in order to preserve or not modify the tones and/or colors in the process. Yes, it's a pain, and takes time, but it's all a personal preference. Just like using Tri-X over Pan-F.