Pulled up my notes from when i brewed this recipe with WY1450 in 2013. OG: 1.054, FG: 1.020. So, 63% apparent attenuation. Sounds pretty similar to what you guys are getting 3+ years later.
Here's the fun part which I forgot all about until I just pulled up my notes: (quoting myself from this thread in 2013, adding bold for emphasis)
I used that same packet of yeast for three SMASH APAs! (possibly a Rye IPA as well, but that's less likely based on brew dates). Here's the numbers for those batches:
OG FG Att. Style
1.059 1.009 83% (APA)
1.052 1.013 74% (APA)
1.077 1.015 79% (APA)
1.058 1.011 80% (Rye IPA)
So, attenuation was fine (even great) on the other batches, from yeast that was built up from the same packet, same starter!
Most recently, I did an imperial stout with WY1450 OG: 1.095 FG: 1.025 72% apparent attenuation. I have to put big asterisks by this batch though. It was an expired package of yeast that i got from free from LHBS and built up with a multi-step starter. The wort was the second runnings of a two mashes for a bigger imperial stout AND my temp controller flaked out a couple days into fermentation and dropped the temp to almost freezing.
So, I might believe that 1450 has lower attenuation with lots of specialty malts as this recipe has, and I might believe that it is more sensitive to temperature than other strains, since I didn't have great temp control in 2013. But I don't quite buy that's it's a chronic poor attenuator or that a recent "bad batch" caused low attenuation.
Here's the fun part which I forgot all about until I just pulled up my notes: (quoting myself from this thread in 2013, adding bold for emphasis)
Getting ready to make this one today.
I guess my LHBS is better than many, no problem with any of the ingredients, and they have a good mill that i get great efficiency with. I decided to go with Denny's Favorite for the yeast, i have a huge starter going that i'm going to split, use half here, store the other half.
This makes for two of Yooper's recipies in a row, I made the broken leg amber about a month ago, and if i get a line assembled for the keezer in time, i may tap that keg and have a glass of it while i brew today.
I used that same packet of yeast for three SMASH APAs! (possibly a Rye IPA as well, but that's less likely based on brew dates). Here's the numbers for those batches:
OG FG Att. Style
1.059 1.009 83% (APA)
1.052 1.013 74% (APA)
1.077 1.015 79% (APA)
1.058 1.011 80% (Rye IPA)
So, attenuation was fine (even great) on the other batches, from yeast that was built up from the same packet, same starter!
Most recently, I did an imperial stout with WY1450 OG: 1.095 FG: 1.025 72% apparent attenuation. I have to put big asterisks by this batch though. It was an expired package of yeast that i got from free from LHBS and built up with a multi-step starter. The wort was the second runnings of a two mashes for a bigger imperial stout AND my temp controller flaked out a couple days into fermentation and dropped the temp to almost freezing.
So, I might believe that 1450 has lower attenuation with lots of specialty malts as this recipe has, and I might believe that it is more sensitive to temperature than other strains, since I didn't have great temp control in 2013. But I don't quite buy that's it's a chronic poor attenuator or that a recent "bad batch" caused low attenuation.