given a speed restriction of 270kts or less when he was cruising at FL400 and at least 30 miles from TOD. The pilot flew at mach 0.85 (or something similarly high) until FL230! IAS was around 340kts if I remember correctly. His excuse was he hadn't transitioned to IAS yet. This too makes no sense to me. 270kts or less is 270kts or less. It applies at any level, even when flying with reference to mach
At FL400 M.85 is close to 270KIAS. FL200-250 is generally where the Mach to IAS conversion will take place when doing a normal conversion from M.85 to 310 KIAS or M.82 to 290 KIAS or similar. You need to get your head around the Mach/IAS relation at high altitude.
You also need to learn more about the airspace outside your own little box. If you don't understand your adjacent sectors, how can you provide good ATC "services"?