If you are interested in a hard core fitness opinion that is delivered with a tongue in cheek style, I’d suggest you check out Scott Helsley’s Ration Fitness Blog.
His recent post on the use of Jumpstretch Bands for training included this photo.

It is not uncommon for athletes to dynamically load their bench press, squat, deadlift, or dips/chins, it was the angle of pull that was interesting. Scott choked the band to a kettlebell far back from his center of gravity. As most of you know, the lats have a wide range of movement. I primarily think of "down and back" when I think of using the lats. Other’s think of using a pulldown machine for endless "lean back pulls" with ridiculously light weights in their local Bally’s. Scott’s arrangement passed several simple tests for my ever inquiring mind. One, it looked challenging and different. Two, it was bare bones cheap. It also fit the "prison mentality" which is a huge component of my personal training philosophy.

On the first try, the answer was simple, … This is an incredible exercise. I think it provides a nice, anatomically sound, pulling movement. The pullups felt different than anything I had tried before. I kept the angle of pull exactly the same for every set, changing it remains as a neat variable for future workouts. The bonus part is when you can no longer pull yourself up. You have several choices. The first is to use a lighter band. The second, use NO band. The third, choke the band onto the chinning bar and step into it for assisted chinning. What about the fourth option? That option is the lat shrug. It is a simple motion that can occur when the arms can no longer bend ( the weakest link in the chin / pull up ). You simple contract the lats by pulling the shoulder blades down and back. In this case the band arrangement provides incredible resistance for the motion. Actually it feels almost perfect. It’s so good that you could actually use this as a separate exercise. That’s what legendary Mr. Olympia Larry Scott did. He learned the exercise from sword and sandals actor, Mark Forest (Lou Degni). Forest would actually put his wrists on the bar and not use his fingers. He felt this isolated the lats. I don’t personally think it makes a difference. If you choose to do it without doing the pullups first, use a heavier band, and really blast out the reps. You can move quickly since the band dampens momentum. I think higher volume in this case would be a nice change of pace from low reps and sets. Any numerical variation of sets and reps should work however. Be creative. The results could be stupendous. Look at Scott’s back.