My guess would be because he thinks a rally could occur once the pause takes place. These stocks are very undervalued at the moment. I have spoken repeatedly about the odds being better about shorting stocks with higher valuations than these. I know the one guy claims to be making a mint shorting these, and maybe he is.
However, a guy like Fleckenstein takes postions for long periods. He wants to develop a big picture view for a short, and then sell on strength into that position. He will then more than likely add to his shorts on strength and hold on come hell or high water. He is not a momentum trader.
However, this is just a guess. I do not know him, even though I think he is very sharp. His track record is pretty good.