In the beginning there was one certifying organization that was the very demanding LA Co UW Instructors Association who created the world's first certifying program, the Underwater Instructor's Certifying Course commonly referred to as "UICC"
The course required a D&R at 33 plus feet and a free assent (aka CESA) from 100 feet.. Every one who passed the course performed a CSEA with out any problems.
"Practice under controlled conditions what you may need to do under emergency panic conditions"
In1967 LA County developed the world's first Advance Diver Program the three months long "ADP. " It require the student to perform a free assent a "CESA" from 33 feet.
The program also required the students to maintain a LA Co dive log - the first time a dive log was required and it was the second dive log ever created-- The first Dive Log was created by the late Dick Bonin in 1955 while employed at Dive Master, and who later founded SCUBA Pro in 1963- Lets give credit were credit is do...
Dick as an USN officer under Doug Fane (read his book The Naked Warriors or view the movie - Zale Parry is Doug's daughter) They were testing regulator performance under the artic ice and Dick's regulator froze - he made a free assent under ice from 200 + feet
Every diver I certified in 28 years of instruction as LA Co, NAUI, PADI CMAS and other certifications all did a 33 CSEA as part of Catalina dive experience. Not one had difficulty.
While training and diving with my young son, what seems like in retrospect every day and night, I made a rule that he could only dive as deep as he could perform a free assent CESA. I rescinded the requirement at 66 feet -As an adult pre med student Sam IV and Jeff Bozanic were drilling 300 & 400 foot holes in the Pacific -Good training pays !
I have made innumerable free assents CESAs from 100 and one from, GOK, how many feet ? when my regulator and lift bag became one and away I went all tangled and dangled to the surface,.
Today, my age but with my long history of CESAs I suspect any reasonable depth, that a bath tub could be filled with water--but once perfected CESAs should be an automatic reflex , so who knows --But I still recall the LA Co motto "Blow and Go; Flair and you are There !" --
I am going to the beach to walk my dog Lucky and not to attempt a CESA
Sam Miller, 111