(Photo Credit: Bernd Uhlig) Deutsche Oper’s Ring Cycle started promisingly with an original staging of “Das Rheingold,” with provocative ideas, irreverence and even humor. However, unfortunately it continued with a constant rehashing of ideas, which proved inadequate for the gigantic enterprise that is Wagner’s “Ring.” After a vocally satisfactory but scenically uninspired “Die Walküre,” matters deteriorated considerably on May 29 {…}