The technical info is mostly fine, but the advice is nonsense. Have a look under "recovery techniques", where we are advised how to recover from a wake turbulence encounter - however this information contains the rider "Note that this technique is primarily designed for wake turbulence encounters for aerobatic aircraft manoeuvring in tailchase or dogfight conditions." WTF does that have to do with GA? The methods suggested could be quite dangerous for inexperienced pilots, particularly when you consider that earlier in the article, we are told that most Wake Turb encounters take place in the takeoff or landing phase, below 200'AGL. Nowhere in the article is there any advice on what to do if you encounter wake turbulence at low level during takeoff or landing, in a non-aerobatic aircraft with limited power. In other words, they have completely misread their target audience. Just another example of disconnection between the regulator and the operator.
BTW it isn't really that big a deal, most people will instinctively roll upright the quickest way. Trying to apply rehearsed recoveries in wake turbulence encounters is problematical!