What it draws
From the cash open it projects two radii on each side of the market. Built on overnight and open-to-close structure across recent Globex days, not a close-to-close shortcut that throws most of a 23-hour session away.
The day is not a constant
A fixed 0.5 radius is tagged on 60% of sessions in one volatility regime and 32% in another. The same line meaning two different things. MM Radius scales Z1 by overnight activity and the current vol level. Walk-forward, that spread collapses. The overall tag rate stays near half.
One re-read the data allows
At 10:00 the first thirty minutes can re-weight the remaining range. That opening window predicts the rest of the day better than history does. The gap skew is off. Tested four ways, “off” won. It was clipped at its bound on three quarters of sessions anyway, a fixed tilt pretending to adapt.
What it will not claim
A single day’s excursion is about four percent predictable from anything known at 09:30. The study does not chase the high or the low. It keeps the probability of a touch honest. That is a different, and achievable, job.