Do NR7 volatility contractions predict profitable breakouts?

We want to buy breakouts that come out of volatility contractions, using the classic NR7 (narrowest range of seven days) pattern. A bar is "NR7" when its high minus low is the smallest range of the previous seven bars including itself. Enter long the next open after a day where today is an NR7 bar, yesterday was also an NR7 bar (so two NR7 bars in a row), today's close finishes above today's open, and today's close is above the 50 day simple moving average. On entry, place the protective stop just below the lowest low of those two NR7 bars. Size the position so a stop-out loses exactly 1 percent of account equity. Round down to a whole number of shares. Take profit at 2R, twice the distance between entry and stop. If neither the stop nor the target is hit within 15 trading days, exit at the next open. Long only. One open position per ticker at a time. No leverage and no pyramiding.