Session filters: why the same pattern fails at different hours
A breakout that thrives after the Australian cash open can wilt in the overnight thin tape. Filtering by session is part of technical analysis training, not an optional flourish.
Pattern names travel well; liquidity does not. We regularly see students apply an opening-range idea to every clock hour and then wonder why the historical table looks noisy.
Split the workbook
Run two columns: instances inside your intended session and instances outside it. Compare outcomes before you merge them into one proud percentage.
Respect local calendars
Australian public holidays, early closes, and US holiday eves change participation. Tag those days instead of pretending every Tuesday is identical.
Do not hide the filter later
If the setup only works in the first ninety minutes, that constraint is part of the edge description — not a footnote you omit when talking about results.
Group chart labs often use a single morning window precisely so participants feel how session choice reshapes entry counts.