This is the epitome of a big man pass. It may actually be my favorite pass against people who just try to keep their legs closed.
If you have ever relied on using your elbows to open the inside of the thighs then this is the pass for you! Just replace this pass with any time you would have done that pass!
Although this pass is extremely simple it does have a technical aspect to it. Make sure when you take grips on the upper part of the pants that you keep your arms locked out. Please take take note on how my elbows are angled so that you are not in danger of getting armbared.
As I start to make space backwards I do not, under any circumstances, bend my elbows. If you do bend your elbows you will lose all of the leverage that you have been building by moving your hips back (and you'll probably do a face plant on their chest when they pull you forward too).
Once the legs have opened you can really choose any of your favorite passing methods. I prefer to get my knee up in the middle and start from "combat base". This allows me to assess the situation without allowing my opponent to re-close his Guard.
as a note, if you are having problems with this pass it is probably because you are bending your elbows....so I suggest you stop doing that.