Buying and holding volatility usually hurts; then came 2018

NEW YORK (Reuters) - The big uptick in stock market gyrations this year has made a surprise winner out of a trade that has rarely delivered a win - buying and holding volatility.Stock market ructions over the last decade have been few and fleeting, requiring great feats of timing to generate profits from volatility buying.Not so this year. Frequent bursts of market gyrations have kept things lively in the volatility space and has made betting on enduring turmoil hugely profitable.While the S&P..