Dogma wrote: <<But.... is it not feasible to have the "no speed restriction" information just prior to take off? >>
No disrespect intended, but I feel this highlights the ignorance some pilots have of ATC operations - and I've no doubt that they can justifiably say the same about our knowledge of their job too. Many pilots do not appreciate just how fast an air traffic situation changes and that minute or so it takes you to get airborne could be crucial. What if you're 2 minutes behind an A340 and you were both given "no speed restriction" before take-off? The A340 climbs about as fast as my old Reliant Robin while you hurtle up to 300+ (presumably). It would make life rather exciting, believe me, and the amount of paperwork when you hit him.... you just wouldn't believe!
As I said before, plenty of pilots are more than happy to accelerate at low level, which again highlights the varied operating practices between different crews on same type, even with the same airline.