Makes sense, there's more to bittering than just extracting AA, put a hop pinch between your cheek and gum and you will see that it is plenty bitter with no boiling what-so-ever.
I have heard this same information out of the Brewing Science guys at UC Davis....the brewing software will continue to compound the AA numbers in the recipe but it doesn't seem to correct for what is observed through lab analysis.
The commercial guys can crank up the IBU's with hop extract, and since they have labs handy they can do it in a controlled, precise manner.
Something is always fermenting....
"It's Bahl Hornin'"
Kegged: Sour Saison, Pale Ale, Aggie Ale, Firestone DBA, De Koninck Blonde
Bottled: Belgian Quad (Grand Reserve), Derangement (Belgian Dark Strong)
On Deck: Pliny the Younger