That other time was against Filho. Think he learned that from Matt Lindland.:yep Fortunately Silva didn't fall for it.
It was a triangle/armbar combo but more armbar then anything watch it in slow mo theres no pressure on Sonnen's neck and head area anymore at that point infact Silva's got a big gap inbetween his legs thats why Sonnen slips his head out so easily after he taps despite Silva cranking the arm for all hes worth.
He did the same thing against fihlo.. Chael was screaming TAP.. then the ref stops it and he claims he didnt tap. He's a poor sport.