[quote]But for the sake of argument, what else could affect aroma?
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Well, your hops amounts are pretty low for the aroma addition. But, according to your other, recent post:
You might try fermentinga little cooler. Fermentation by products do mess with the aroma and, also, an extremely vigorous fermentation may blow out more hop aroma.
But … that said … you also need to use more hops!! 