Merdeka: sorry but not true.
ATC don't need to know all the manoeuvre speeds for all the A/C in their airspace on approach. They have a pretty good idea what we need but.........
How many times have you been told to reduce to 190 kts, and 190 kts was about 5 kts too slow for Flap 1 so you had to take flap 5.
So by your account they should know exactly what speed I need for flap up through to 30 and for every landing wt for my 777,give me a break, these speeds can vary by 20kts.
Sometimes they get it right and it's just a fluke, nothing more.
They slow ya down to what they need for spacing.
What do you think they will do if a 747 is following a 737? use the 737 flap maneuvering speeds or the 747's? mmmm
"the 747 needs about 230 kts clean, so lets get the 737 to hold 230 kts as well"
They give you what they need, and if you need to take more flap that's your problem, not theirs.
And to suggest they should know our landing weights and work out the speeds?????????? you must be kidding? they don't need to know that.