How do you know those weren't pooled blocks? We had sellers today. If the selling is simultaneous you're going to see larger blocks here and there. Maybe somebody in the crowd had more to unload than the rest - but my point is that, when you move into an A/D range, there is usually an increase in volume. Thats all.
Anyway, 100k blocks aren't very big. Also, people generally unload much faster than they accumulate.
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