Demo fills are polite. Live costs are not. I use demo to rehearse hotkeys, workspace layouts, and flatten paths under fake stress. I do not use demo expectancy to decide whether a scalp edge survives raw commission and slippage on a real book.
Desk split I insist on:
- Demo: execution hygiene, layout, news-flatten drill, muscle memory.
- Live tiny size: cost logging and emotional reality — including the urge to overtrade.
- Only after a live cost sample do I discuss whether the setup is viable at normal size.
How long do you run tiny live cost sampling before you trust a setup out of demo?
Demo can still be useful for rehearsing news flatten under a timer. Just never confuse rehearsal fills with a broker scorecard. Different physics, same buttons.
