DP. Sorry didn't see your post
Of course, one wishes to maximise the landing rate to reduce delays. Trouble is, we've done that for years and so now the bean counters take it for granted and schedule a load more. This uses up all the spare capacity (which is a safety/service buffer) putting Heathrow in the position it is. If a service/safety buffer had been insisted upon over the years, the third runway decision would have had to have been made 15 years ago. Spare capacity is not waste - it keeps the operation robust in difficult times and that serves everybody, airlines, ATC, and Pax.
For this reason, the capacity gains of mixed-mode will not all be given to scheduling. At peak times the majority will go to reducing delays but greater increases in scheduling will be permitted off peak; the airlines have bought into this principle (for now at least).
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