Wyckoff trading method, page-1128

Interesting comparison between AHZ and NRT, I believe in similar sector, biotech, both had previous lower volume upthrusts of similar size to the following higher volume upthrust, large spread bars no doubt containing plenty of selling or weakness, but why the difference in volumes over similar spreads and could these bars lead to an exhaustion of sellers? These bars are found at the bottom of the chart, effectively spiking off support, not where you would expect to find them, as part of distribution at the top following a mark up. Is this a sign that one or more SI's has cut their losses and moved on, possibly removing a potential future handbrake?
NRT went on to 4 bag from here before later dropping back to support where it currently sits but I thought it was an interesting comparison.
I've included the comparison weekly charts below, Charttrekkers not the best as its limited in ability to setup bars with no open etc. but it's really quick to use, good for multiples