Wide grip, machine assist, full-range pull-ups you can actually progress.
More assist weight makes it easier, lower slowly and chase full range over big numbers.
The wide overhand grip shortens the biceps' ability to help, which is exactly the point, the lats have to carry the pull, and the assist stack makes full dead-hang-to-chest reps possible while they learn to. Elbows driving down and back through a long range is what builds width, and the machine lets you accumulate that quality volume long before bodyweight reps exist. It earns its place as the back-width builder for anyone still earning their first strict wide pull-up.
The wide overhand hand position takes your biceps mostly out of the movement and shortens the lats' leverage, so your back does nearly all the work through a tough range. That difficulty is also why they build width so well.
Just outside shoulder-width is plenty, hands a few inches beyond your shoulders. Going extreme-wide cuts your range of motion and stresses the shoulders without adding lat work.
Both train the same pattern, but the assisted machine keeps you moving your own body through space, which transfers directly to real pull-ups. Use pulldowns for extra volume, use the assist machine to chase the unassisted rep.
