True, but you also have latents and trials that do care about closing skillchains. This shows how you can attain certain levels using SCH. Its better to have the information and know it's limitations than it is to dissmiss it off the cuff.
I can understand mentioning the staff bonus, becuase changing staff will reset TP to 0, but you can change Obis in between.
Also, these are all tools. Knowing the correct tool for the job can help with specific goals. The situation you are using your tools for general nuking. I can understand wanting the Staff bonuses per nuke there, because it will be a majority of what a nuking SCH does. But what if your goal is to max a Helix? (God knows that's one of the things I want to do with SCH!) Spec for the Helix weather, build up to a lvl 3 Chain and let the Helix fly. Heaven forbid our nerfed Modus Veritas lands afterwards. /squee!