Mutual funds are sitting on so much cash that traders have taken it for granted that they will emerge as buyers whenever the market falls and help stage its recovery. So when the Indian markets fell the most in 10 months on Friday, most traders — according to Samir Arora, a popular hedge fund manager — were left singing, “Kya hua tera vaada/Woh kasam, woh irada (what happened to your promise and intention)” from the 1977 hit Hindi film, Hum Kisise Kum Naheen.