Criss,
The delays that your quote indicates would be unacceptable at any modern aerodrome.
There are two different ideas being discussed here. You require runway separation in order to launch an aircraft, but you also require some protection against the landing aircraft making a missed approach.
Your quote is referring to protection against missed approaches, but it is very restrictive and I'd say it's referring to procedural control where the tower controller does not have the arrival in sight. Good visibility and/or a radar can change the equation considerably.
Pera