OK, the data rates I saw when connecting my MacBook Pro via Hotspot to my iPhone 5s.
1. For years it was 200-800 KB/sec when connected
2. ATT sends me a note I am over my data limit and data transfer goes to 4-20 KB/sec
3. I go check out info at the ATT store and up my data plan
4. Data speeds still 4-20 KB/sec (Activity Monitor)
5. 2 More trips to ATT with all the excuses: Heavy cell traffic, Poor reception at your house, interference, etc. (even though nothing had changed at home)
6. Final ATT guy says "Let's reset your network connection in your iPhone." One restart and data connections routinely now go up to 200-900 KB/sec as needed.
Is that enough proof. It is just a data rate after all.