I have never filled out the online survey that arrives via email, usually within a week of a IHG stay. However, I just received a survey for my most recent stay and felt compelled to give them a frosty talking to

....to my surprise there is an entire section about Priority Club, as it pertains to this hotel, and if you rate it low they ask you to elaborate by selecting from a list. The list contains (not in the right order) 1/ Status Recognized, 2/ newspaper outside room 3/ offered complimentary upgrade 4/ offered 2pm late checkout and some other things.
It appears that, even though upgrades are not guaranteed, they are rated on this.
So, I highly recommend everyone fill out the surveys if PC status was not recognized and PC benefits not offered.
I'm sure you all knew this, but i'm on a roll tonight, so humour me
ciao ciao
jrs