Thanks to Mrs Jerricho, she has convinced me (as well as Bren and Binos) not to fire off an email to the editor regarding this sensationalist tripe.
Del Prado, interesting comments there about points to learn from.
Garbling (label overlap) is a problem. So why do NATS pursue a policy of minimal flow restrictions and therefore maximum airborne holding
Yes, lable garbling does occur. However, as Hammy indicates, that's why flight progress strips are also used (or whatever form of flight data recording and display), thus making it a non issue. In fact, the Heathrow Int Support controller often manages the stacks "procedurally", using pilot reports of leaving levels and maintaining to update flight data information. IMHO, I think it emphasises the need for accurate and legible flight data recording.
And regarding NATS flow policy, we all know flow control isn't an exact science, and all manner of variables can cause a 10 minute inbound delay to increase to 30 minutes. Conversley, if weather factors change or TEAMing is put into force (using both runways for arrivals) a landing rate can increase considerably, eliminating all delay (and leaving no jets to play with).