Chart, page-20337

The flag formation near the top of the large move is in itself a pattern that indicates 'hot' market. If conditions persist (like strong macro drivers, anticipated positive comp ann materialises, etc) the flag will break upside.

Normally you don't get flag formation (or very short lived one) in neutral/negative market.
You get exhaustion pattern on the top (exhaustion gap, double top, head and shoulders, rising wedge, etc)
And the SP comes down with an elevator half way or the base of the move. There it attempts to form a new pattern(double bottom falling wedge, etc) if it's attempting reversal or continuation pattern if selling pressure is to high (rising wedge, bear flag, etc)

So: you make a good point, but the conditions you describe are already woven into pattern.
As always: pattern is only as good as conditions that formed it persist. Any strong macro/company specific development will break the pattern either direction.

That's in a nutshell basic explanation.

From Beisha chart, in a nutshell:
-flag formation over 2-3-4 weeks, holding above 2.6: strong conditions persist = high chance of upward break.
-2.60 falls through - strong conditions cooling off = look for new pattern formation around 2.2 (usually more protracted or volatile moves).

Hope that helps