Channels do not negate triangles. You can have both. The SPY follows the same technical analysis "rules" as any other chart. Except the chart patterns and indicators are even more reliable on the SPY, because there are way more data points than a single stock... 499 more to be exact ;)
Triangles are extremely rare on the SPY, because it is normally trending, or in a "channel". This is VERY important to note, because this means that the market as a whole is in a state of indecision. That's what this pattern is telling us. So, it would be wise not to throw out this pattern just because you don't really see it that often on the SPY. In fact, you/we should be doing just the opposite... pay closer attention to something that's so rare on the SPY.
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