I requested him to fly not less than 270kts. Imagine my surprise to see him accelerate and threaten to catch up the bunch in front. When questioned, he reported his indicated as 325kts! This into a 10 minute hold that he had been told about and was an increase of 55kts from the speed he had previously been flying!
I fully agree it's not good airmanship but he actually didn't do anything wrong. I would suggest it would have been better to leave the speed at 270kts or even 250kts and allow the gap to be maintained and maybe allow some of the airborne holding to reduce.