Stealin' is the b-side of Breakthru' (can't they spell!!!!). I think started by Brian but finished off by the rest of the band it certainly sounds like a jam.
I've heard a twelve or so minute version of it and it doesn't get boring. A very good song.
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...and my own opinion - this is one the best their tunes from The Miracle days and that 11-minutes improvised jamming demo is great too.
P.S. According to Sebastian who accorded to Mack (though I don't know how he was invlolved in this track) - it's Freddie's track.