Never measured a pH.
Never whirlpooled, don't know what it does or why.
Never used non homemade vessels.
Never used a plate chiller.
Never made a lager (shortly to be rectified.)
Never fly sparged.
Never worried about trub in the fermenter.
Never used a refractometer.
Never kegged.
Never autosiphoned.
Never followed a recipe exactly.
Never brewed the same beer twice.
Never acidified a mash.
Never used a secondary fermenter.
Never had the patience to wait until a beer is 'ready' before drinking.
Never used a pump.
Never added fruit/wood chips/spices to a beer.
Never quite hit numbers and worried about it.
and last but not least...
Never made it through a brewday without leaving a damn tap open somewhere along the way!