Pension funds promise 8% returns

Normally, 8% covers inflation and a small positive return, increased by tax reliefs.
As we are now in a deflationary spiral real returns of 2% may still be good as the price of most things may be dropping by 2%, making a 4% "after flation return".

The real challenge is whether the investment managers will be capable of making a positive return, given that stocks will be declining, in fits and starts and a 30% loss in a month may be possible!
Going to cash or Govt bonds may be the only way to avoid the expected falls.

The lying about 8% worries me not. They lie all the time about OPM!