2659 or better potential for SPX based on measured moves

The way breakouts typically function is with measured moves as a way of determining how far price will move until it reaches its climactic point of selling. In this case, I measured the range of the top to bottom in our past 5-7 trading sessions and determined that 2659 would be a decent level to cover some shorts or initiate a long day trade idea. Heres why, the length of the move will coincide with central bollinger band, thats the only technical indicator I used. Also moves tend to overshoot so this measured range of 15-20 points may blow straight past my target. Lets check in on this idea later and see how it worked.