CONTEXT, CONTEXT, CONTEXT !
Thirteen,
your example merely shows that for small-range moves, SB is INAPPROPRIATE to use in the manner described.
Since you know that the spread, in your example is 6 points, you would seek out opportunities that exceed that, such as EOD or swing-trades.
You would not trade markets where the profit target was 6 points or less.
Your example is therefore misleading.
SB does work, as long as you use it appropriately, in the context of the instrument traded, the volatility of the instrument, the margin required, the risk of trade, potential reward.