When it comes to historic architecture, Minneapolis city officials have long exhibited a penchant for knocking stuff down rather than preserving it. But we gotta say this for them: When they do set their minds on saving an edifice, they spare no expense. Enter the Shubert Theater. The city spent four million dollars to trundle what remains of its exterior a quarter of a mile on Seventh Street to its new roost on Hennepin Avenue. And that ain't all. Now that the relocation of the 1910 structure has been accomplished, rebuilding the place is expected to cost another $26 million. The move occasioned so much civic giddiness--we're gonna be in the Guinness Book of World Records, fer chrissake!--that you'd have thought we were raising the Titanic. All the bureaucratic back-patting proved to be an effective smokescreen, obscuring the bumbling and neglect that have completed the transformation of the Shubert's original home from prime downtown real estate to an open sore.