I think he meant you need a perspective on the market in order to trade, flag being one reason to enter for some people (opinion). So you "would care about the prior pattern.." Others will just buy and sell in the now, based on other criterias, ie. ETFs will always buy and sell regardless of patterns - even disrespecting the patterns? What's missing are all the other hidden reasons to make trading decisions, both technical and fundamental ones Ie. any type of fund may have various criterias, also regardless of patterns, though still more or less valid. The foundational misunderstanding of price patterns being everything, or even relevant. Still, good query!
He could be #100 for all I care. I don't trade chart patterns and I can't give a fair comment on what he advocates or make any comparisons. The only thing I appreciate about him is his willingness to research win rates of the various chart patterns and publish his research for all to see. In an ocean of peddlers of hope, he stands out for that. Peter Brandt has traded for what, 40 years? He is open about his overall win rates but has made no attempt to apprise people of what sort of win rate to expect from any pattern, just a vague suggestion of which work best. Al Brooks drones on and on about H1, H2, H3 and so on. Four books, he supposedly trades, not a peep about what to expect. Yet there is no shortage of experts advocating the importance of maintaining detailed statistics on precisely this aspect of trading so one can refine. Easier to sell hope and dreams than it is to sell reality. Reality is the only reason I read Bulkowski's stuff.