Mutual fund investors are warming up to the idea of investing in schemes with concentrated portfolios to rake in extra returns. Investors have become extremely wary of schemes after schemes holding the same prominent stocks in the name of diversification. Motilal OswalBSE -0.77 % Mutual Fund's impressive performance also caught the fancy of many investors. Cashing in on the positive sentiment, BNP ParibasBSE 1.95 % recently launched a scheme with a concentrated portfolio. Are mutual fund schemes ..