People have been lifting for a really really long time and there are multitudes of variations on so many exercises that are done “just because.”
Meaning, we hear phrases like “I do this (BLANK exercise) just because, so and so taught me this way.” Or “I do this (BLANK exercise) just because I feel a burn.” This line of thinking really shouldn’t be in our vocabulary as professionals.
All movement, whether weight-training or not, comes with a risk-benefit question. Lat pulldowns are one of those that seem to have a greater risk than benefit.
In human movement there are some basic anatomical shapes that we assume. At our hips and shoulders flexion is always accompanied with external rotation, and extension is always accompanied with internal rotation. The obvious problem with behind the neck pulldowns is that we have a shoulder that is going into extension but is allowed to go through internal rotation. Basically, the external rotators in shoulder kind of act like a hinge on door and when we do behind the neck pulldowns we are just tearing at that infrastructure.
Now, I get the whole big lat thing. I do. And maybe some people really need lats (i.e swimmers, aesthetic athletes….). I come from a place where we don’t do what is unnecessary and at a greater risk. Most “common” folk sit all day and do present with shoulders that roll, meaning the lats will likely be tighter and impede on regular movement abilities.
Again, that’s me using biomechanics for the average person.
Hope this helps,