So I tried the 35 degrees 48 hour technique, except that I got too busy (newborn) and ended up letting it go 7 days. It was in a bucket, so I didn't see what it looked like, but there was a little hop matter in the first few pours, so I assume that it dissolved okay. I have to say that I got decidedly less aroma than I would expect from the hop addition I used, though it was not a huge addition and it is not an otherwise super-hoppy beer (it's a riff on Denny's Waldo Lake Amber Ale recipe -- smaller gravity and a touch darker/maltier than the original and with Eureka/Chinook instead of Cascade/Centennial). I only added 1 oz dry hops, but the finished beer seems more like I used 1/2 oz or maybe 1/4 oz. It's fine -- I wasn't even going to dry hop this beer, so there's really nothing lost to me here, but I would hesitate to try this on an IPA where I might be under-utilizing 4-6 oz of wort-absorbing aroma hops.
I will probably try it again in a blonde ale or a bitter or something else that doesn't have a ton of aroma hops in the kettle, but so far I am wondering if Denny's success with this technique might have something to do with his using cryo hops.