All indicators positive but leaders are weak–sell in May?

GMI6/6
GMI-26/9
T210871%

While all of my indicators remain positive, my group of nine high priced leaders has been weak.   Only 4 of them remain within 5% of their 52 week highs.   Four are around 10% or more below their yearly highs (CMG, BIDU, GOOG, FFIV). Some of the speculative commodities are also weakening.   I am more cautious when the leaders are weak.   I remain largely in cash in my trading account. Will “sell in May and go away” work this year?