I highly favor the open guard in my BJJ practice. I think at one point you could probably have said I was an "open guard guy"
Some thoughts.
Many opponents wear clothes.
Spider guard DOES work, but the pace is much faster.
You cannot "hang out."
The last point is where people usually make their mistake. Because of the gi, they are used to "hanging out," in open guard positions, setting things up carefully, then doing whatever it is they are going to do.
I sweep constantly from open guard without a gi, but you have to be willing to open up and go for things....and you have to be willing to use the offbalancing created by your sweep attempt to come to your feet or otherwise attack.
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