Most traders practice by scrolling a chart backward and eyeballing entries in hindsight. It feels productive. It isn't. The moment you see a clean setup on a historical chart, your brain has already processed the outcome — the candles following the entry are visible in your peripheral vision, the structure is resolved, the uncertainty is gone.
Deliberate practice needs uncertainty at the decision point
True deliberate practice requires uncertainty at the point of decision. Bar-by-bar replay restores that. You don't know what the next tick looks like. You have to manage the trade in real time, including the uncomfortable part where price moves against you before it moves in your favour.
That discomfort is the part scrollback removes, and it is the part worth practising. Sitting through an open position that is down is a different skill from recognising a pattern, and only one of them can be trained with the answer already on screen.
If you want the repetitions to add up rather than just accumulate, it is worth reading how compressed practice time changes the arithmetic, and how to structure a session so each one answers something.