User blog comment:Wolf night10/The Final Getsuga Tenshou/@comment-1961713-20100610141100

Maybe because of Experience, or He has fully Mastered the Final Getsuga Tenshou, he could easily summon its power without releasing. Experience do contributes greater knowledge.

But what do you mean 'not really an attack but more of an attack style' obviously it is the same here does it?

Getsuga Tenshou are not the same like a Cero, because in order to acquire this power Ichigo had gone through the Shafter Training by Urahara, where you first learn his zanpakuto's name and then proceed. it is a zanpakuto techniques only to be learn by its wielder. I may be against the site's policy in stating that Isshin may wield Zangetsu too but until the chapters otherwise stated or explained this we cannot be sure at this moment.

While Cero were much like Kido techniques where you can learn this as a student or be taught in general in some sort of school. It can be used by many, while techniques derived by wielding a zanpakuto are different and unique. So in saying that this is a capabilities displayed by a member of the Royal Guard maybe inaccurate.

If only Ginrei Kuchiki's Shikai or Bankai was explained previously revealed as same as Byakuya's then we could say Getsuga Tenshou was indeed a family treasure handed down to by family generation, it was the closest as we would to understand Isshin's and Ichigo's Getsuga Tenshou.