Hmm. I tried "refresh" for the first time during my trip this past week and was quite successful.
I had 2 people which of course makes it easier than with a larger group.
I think one thing that helps or hurts if what attractions you're looking for.
For example TT is gonna be much harder to get than Soarin'.
SDD is gonna be much harder than TOT.
We had success getting Soarin, TT, Figment, and TOT for times that lined up exactly how we wanted.
It was not difficult at all. we literally just kept hitting the same time over and over while walking and things would pop up.
There was a 15 minute wait for Figment so we stood outside of the line for 2 minutes and one popped up for 5 minutes later so using the 5 minutes grace period we entered the line immediately.
We sat at Canada for a few minutes after having some soup and decided to check for TOT before heaing to HS and within 2 minutes we found a window for it that opened in 30 minutes which was great since that's about how long it would take to get over there and in the park.
The wait for that was 45 minutes and we breezed on by the SB line.
If nothing is available then nothing is available and we are not spending more than a couple of minutes to check. I wouldn't obsess over it or it would put a damper on the trip.