Most definitely. You can add in; Iwama, Aikikai, ASU, Yoshinkan and....Tohei's group just in my experience alone. Not to mention Karate, Judo, Daito ryu, ICMA and FMA to boot.
Just to add a comment to some of this stuff about the diverse groups and the levels of IS.
My initial training was from the early days of the Ki Society and primary teachers were David H Kalama and Koretoshi Maruyama, who was Tohei's first chief instructor of the Ki Society; who by the way, is not related to Shuji Maruyama of Mary's lineage and the founder of the Kokikai in Philadelphia. Since then I have trained with AAA, AWA, ASU, Iwama, and some independent groups that were a mixture of styles. Currently, my waza training is Daitotryu Aikijujutsu as taught by Howard Popkin. Of all those groups, the only two that had any level of IS stuff going on was the old Ki Society and the Daitoryu training. However, neither of them had the level of IS that I have experienced from Dan.
As previously mentioned by some others, Tohei's training can provide for a good basic foundation to help get your foot in the door for IS. However, it does not go to the next level that teaches how to obtain that aiki body. Of the two, the Daitoryu, as taught by Howard, was my first glimpse into what that next level could be - and then I met Dan and he has further opened that door.
So, for those that say their current Aikido training brings them IS, well maybe to some level, but it has been my experience that there is way more to learn outside of the many diverse Aikido communities.