I just listened to the 7–10–14 hopping technique experiment on basic brewing podcast and it was pretty interesting. It was part two of the hopping experiment where the guys, in conjunction with bells brewing, did mash hopping, first wort hopping, and 60 minute hopping with everything else being equal. They then did a blind taste test as well as calculated IBUs and measured IBUs. Part two of the experiment was the exact same but they doubled the hops in all cases. (Cascades). Most of the tasters felt that the 60 minute and first wort hopped beers were very similar in bitterness and hop flavor (specifically, none of them felt that the FWH was any smoother), where the mash hopped beer was very mild and smooth. The Lab measured IBUs showed that the highest was first wort hopping, followed closely by 60 minute hopping, with the mash hopped beers less than half of the other two. The measured IBUs in all cases was also significantly lower than what have been calculated in the recipe (almost half). On round two when they doubled the hops findings were similar. Lots of interesting food for thought. Of course as Denny always says though, personal experience and taste is most important.