Most paper-trading reviews begin with the ending balance. That is the least transferable part of the exercise.

A useful paper test should evaluate a repeatable decision process:

1. **Universe definition** — Which instruments were eligible before the session began?
2. **Entry evidence** — Which observable conditions had to agree?
3. **Risk budget** — What was the maximum planned loss before entry?
4. **No-trade conditions** — Which missing or conflicting signals blocked a position?
5. **Monitoring rule** — What evidence would support holding, reducing, or exiting?
6. **Stop condition** — What market, time, or data-quality event ended the setup?
7. **Auditability** — Can the decision be reconstructed after the close without rewriting the thesis?

Paper results cannot reproduce every live fill, spread, queue position, fee, latency, liquidity constraint, or market-impact effect. A strong hypothetical P&L can therefore coexist with a weak process.

The more useful question is: **Did the method remain coherent when the preferred trade was unavailable, the signal weakened, or the market moved before entry?**

For the next SPY session, define the invalidation and no-trade conditions before the open. At the close, score adherence separately from return. A losing but well-executed test may teach more than a profitable trade that violated its own rules.

Educational only. Paper performance is hypothetical and trading involves risk.