I've previously posted a topic about the various changes in certain songs Queen have performed live and how they differed from the album to live version, specifically Father To Son. Those mainly dealt with lyric changes.
You can see that discussion here:
http://www.queenzone.com/forums/1398632/father-to-son-alternate-lyrics-in-some-live-renditions.aspx
Another example of this is the very different version (at least instrumentally) of White Queen, from the 3/31/74 Rainbow gig. The solo is quite different than any other known live recording. Again, as with some versions of Father To Son, this might be understandable if it were an early version of the song, but the song had been recorded for Queen II almost seven months previously, and all subsequent live versions (after this 3/31/74 Rainbow gig) follow the same arrangement as the album version.
Granted, this is the first known (at least as a recording) live version of White Queen, so that might play into it, and it'd be very interesting to hear any live versions previous to this one, but I'm still perplexed as to why it's such a different arrangement of the song.
It's just another one of those mysteries of Queen live that we might never get to hear the answer to, if in case there is any kind of true answer.
Just something else to be intrigued by.
Kamenliter