Soldato
Yes it's standard, but no it's not usually enforceable. And it certainly isn't something you can sack a member of staff for if they are under such an agreement with a previous employer, as per the post I quoted.
It would be unusual for a company to pursue an injunction on the basis of one of these clauses, as they usually fall a long way short of being legally watertight - they're usually just in place as a deterrent. The link you provided gives plenty of detail to this, you should read it.We got purchased by a very large German company last year who deals with testing and safety standards worldwide, we have all this sort of stuff written in our new contracts to avoid us A. leaving, and B. removing the staff and knowledge they have paid us multiple millions of pounds for and simply setting up another firm after running away with the money, the MDs contracts are even more restrictive, somehow id imagine a company who employs over 20k staff worldwide has rather good legal advice and knows what they can and can't enforce in a court of law.