The 270 kts idea is only a suggestion. It came from some of the major airlines working with NATS to try to reduce fuel burn in the hold and the ridiculous practice of doing 300kts + to get the lowest level in the hold and then fly around in circles for 20 mins. Of course the CTC people were involved in evaluating the ideas, but I don't think anyone won an IPOD for it.
It's all part of being aware of the big picture:
If there is no holding, then don't apply it.
If the aircraft's ECON speed is 290kts and you don't need to increase that for separation then don't.
Why do so many people impose a speed differential of 10 kts (300/290/280) on aircraft which are ALREADY 5 miles or more in trail? If they didn't do that they wouldn't feel the need to make the first one do 300 or more just to stop the back one from falling out of the sky.
How many Ts or Ps regularly assess the delays at LAM by looking at the radar at the stack compared with the 'Less than 20 mins' response derived from the SIS page? Very few planners I've observed keep their tacticals appraised of the delays (10 mins or whatever) on a regular basis unless they are into or just coming out of EATs.
Why would anyone with half an idea of ATC feed traffic at 300 kts into a hold 'for separation reasons'? Sort them out earlier and use headings and early descents to get them at a reasonable speed. Accelerating towards a red traffic light seems a daft idea!