On the example that you are discussing with peterhenders you can see that the area/zone that started as a swing hi @ 4017 held as resistance when challenged @ 4005, 4002, then 4009 before the upside breakthrough to a new hi - so it was always going to be a theoretically / provisionally hi-probability place for a bounce on any pullback test from above it per the technical phenomenon of resistance becomes support as it was a swing hi x 4 area/zone (ie a significant area on the chart where swing points occurred) ...and this is exactly what happened. Daily chart below.
Intraday swing trader @ 30min+ supp/res, & 5min+ sbr/rbs, via 1min+ set-ups
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