I have a few in Minneapolis and the timing you describe sounds about right to miss the bloom. Although you are a south of me. The flowers only last about 10 days or so.

I would guess that if it didn't bloom because the flowers buds were dead that they would still be hanging on the plant or had fallen off around the plant.

thank you ginkonut for your response and encouragement that I'll probably see bloom in the yak this year, the buds are all fat with promise and looking healthy and ready. the plant is my first in ground rhodie and is in its 3rd year, so i'd lost track of its schedule after its original bloom after going into the ground and blooming in '04.
wondering: does pinching back after bloom encourage next season bloom, and i've noted that ph this yr is @ 6.8 compared to 5.5 to 5.8 last yr. would Holly-tone bring it back?

I have several ken janek's too. deadheading definitely helps next years blooms (on all rhodos). I snap the spent flower blossoms off by hand, but you need to be careful to break it off just below the flower as below this are next years buds. You can often see the bumps associated with what will be next years buds below each flower and if you break this off, you won't have blooms next year. It is not that tricky, and once you know what to look for, the flower heads snap off easily, leaving behind the forming buds.
As for Holly-tone, I'm not an expert on how much difference it makes to the ph, but it should certainly help some.

The buds on my KJ are getting fat too. Unfortunately the rabbits or squirrels decided to eat a lot of them this year so there are only 4 left. I put granular sulfar around my rhodies to try and maintain the pH. Actually, I have never had the soil pH tested, but I put rhodies in and they grow. I must have soil they like. I have never tried hollytone, but I don't think "acid-loving" fertilizers affect pH as much as some of the soil acidify treatements do.