Although never intended to be a gentleman's course, such combat diver courses were not screening and selection courses. However in saying such Army Special Forces/Rangers tended to run such courses in such a manner. Particularly during the 1980s. All courses to some degree are assessment courses in that there are pass/fail or go/no-go performance, skills, and knowledge required to be demonstrated or gained to pass the course,
I understand. In comparison to A&S, is the instructor student relationship similar? What I mean is will the instructors be trying weed out people or will they take a more constructive approach to their students?
The intent of such courses that lack specific A&S purpose and intent is to train and not to weed out. The purpose of an A&S prerequisite course is to eliminate need and purpose of training courses to weed out (reduce the number of students) getting trained through a training course curriculum.
Although I understand the perspective in which the question is being asked, the weed out and reduce the number of students mystic, confusion, and BS is actually more connected to Army and Navy who used special qualification courses as getting through such courses as being the best of the best branding due to actual lack of operational capability requirement for MFF parachutists and combat divers in the operational line units. This attitude within the Army began during the 1970s when enlisted were awarded extra promotion points for simply collecting badge by completing the course. Btw the completion of such courses to include Basic Airborne within the Army were not required or mandatory for award of MOS. There is no U.S. Army Ranger or Airborne Infantry MOS and US Army Special Forces had no MOS prior to the mid 1980s (simplified history explanation).
Within the Air Force the only specialty having a robust and officially approved A&S course prior to 1988 was Pararescue. PJ Indoc became a combined or joint CCT-PJ A&S course during the period 1988 thru about 2000/1. CCT withdrew because combat diver and MFF qualification wasn't required for award of 3-skill levwel AFSC.
Until 2019 CCT/SOW (SR) and TACP had 5 or 10 day orientation courses and not a A&S course.
A lot of Army A&S weeding out mentality entered the PJ Indoc course during period 1988 thru 2000/1. To some degree this Army weeding out mentality also entered into the AF Combat diver course as there was influences and desires of the Air Force course is just like the Army Special Forces divers course. A course PJ were going through since 1963 so there is some old timers corporate memory of the Army's weeding out mentality which like as encountered at the Army's Basic Airborne Course was never an issue or problem for any student getting through the PJ Indoc course.
I went through PJ Indoc immediately after completing BMT from Mid Aug 1973 thru end of October 1973. During this period I encountered a full frontal sinus squeeze during physiological training (Chamber Ride) that almost required corrective surgery. A few weeks afterwards I encountered Chondomalsia of both knees of such extent nether knee would support my body weight. The Docs and Instructors took a constructive approach with me and all other students encountering injuries. They also took constructive approach to give swimming and physical fitness training to students.
A lot of BS opinion and history is being put out that exaggerates Instructing purpose is primarily to see how many students can be made to quit. While never an Indoc Instructor I was a MAJCOM/AF Augmenting IG member during period 1989 thru to 1993 and was involved in investigating student grevances, complaints, and concerns. I can assure you student hazing and instructor activities and actions of deliberately focusing on a student or any student to make them quit wasn't tolerated during the period 1989 thru 1993.