I don't think that's true...I saw video clips from the interview with Clarence and there was no mention.
Some guy on the BTX board is claims he is playing Born to Run start to finish in DC and Balt, that I'd like to see. I'm not finding anything to substantiate that though.
Trust me, if Clarence was sitting out a chunk of shows it would be the biggest news on Backstreets and there is no mention.