I was under the impression that So Cruel was played only acoustic, with Bono only.
The song was played four times - the first time it came up pretty much spontaneously; in Milan on May 22nd 1992.
It was rehearsed at Hershey and there is a recording, where we can hear a full band version.
The three nights it was played(acoustically) were Boston, August 22nd, Detroit September 9th and Chicago September 15th.
I went to check if there may have been a full band version on a concert, but a reviewer states on U2tours.com that only Bono played So Cruel in Detroit, on 1992-09-09.
So, where did you get that info?
It would be pretty interesting if So Cruel really got played in full... Although I doubt it, according to the reviewer on U2tours.com and the placement in the setlist(during the acoustic set).