Easy

The old form

The first exercise in Kenkotaiso, as taught by Tohei Sensei: swinging the arms while turning the entire body.

The new form

The first exercise in Kenkotaiso, as introduced by Yoshigasaki Sensei: stretch your arms upwards, angle your hands slightly, and rotate your entire body.

The difference

During a ki-exam in Italy in 2010, when the examinee attempted to demonstrate the new form, Yoshigasaki Sensei asked him to demonstrate the old form instead.
The new form, he explained, is good for practice. The old form is more difficult because it is "too easy"; consequently, one must make a great effort to execute it correctly.