| Bars/day | Bars/yr | gross SR(OOS) | net1 SR | net2 SR | turn/bar |
|---|---|---|---|---|---|
| 10:00-15:00 | 1512 | 1.61 | 0.33 | -0.94 | 1.15 |
| 09:00-15:00 | 1764 | 1.84 | 0.40 | -1.04 | 1.16 |
The 09:00 ET bar is the ~9:30-10:00 opening half-hour (Alpaca hour-stamped).
Verdict: adds gross, not viability
Adding the opening bar lifts the gross edge 1.61 -> 1.84 (opening-print momentum is real) but net@2bp goes -0.94 -> -1.04: the extra bar adds turnover in proportion. Net@1bp barely improves (0.33 -> 0.40). So a 9:31 slot would make the book trade more, with the same cost wall. Not deployable on its own merits; only worth adding if paired with a genuinely cheaper execution.