Yusuf said fellow activists in the square asked him to go, but he made it clear in his comments immediately after their request, (and was quoted in local papers) saying that he did not speak for any movement, and made no deals.
Watch ABC News' Terry Moran's full report on the crisis in Egypt on "Nightline" tonight at 11:35 p.m. ET
This guy is no fake dissident or regime puppet; he's been on the front lines of the demonstrations, and said he would never forget the sound of a bullet hitting the guy next to him Wednesday night. He also said he wouldn't leave the square until President Hosni Mubarak was gone.
But what does "gone" mean?
For some, it means nothing less than President Mubarak in the dock, or on a jet, bound for Jeddah, Saudi Arabia, or swinging at the end of a rope from a lamppost outside the palace.
For others, it means a quiet retirement in Sharm El Sheikh.
For Yusuf, it has to be clear that he is out of the political process.
It's hard to overstate the distrust of President Mubarak and his cronies.
"It's a trick! It's a trick!" one protestor passionately declared when he heard me talking about historic negotiations between the Mubarak administration and the opposition. It's clear that President Mubarak's talks of reform are not enough for the protesters.
And while most Egyptians are heading back to "normal life," I get the sense that they are quietly happy that the hard core protesters remain in the square -- guardians of the revolution, in a sense. In fact, it seemed today that many people just wanted to show up in the square and take a stroll there after work, in solidarity and approval.
But under that degree of normalcy, there's still a lot of tension here despite yesterday's negotiations.
But somebody's got to do the deal. There are always purists in every revolutionary moment -- Trotsky, Che, Michael Collins -- who accuse pragmatists of betraying the spirit of the people.
The pragmatists almost always win.