So I presume the TMA does not use the same computerised system as surrounding sectors? If they did it would be more straightforward as they could simply place the current heading in the label for the next sector to see.
The (London) TMA doesn't have a 'computerised system,' so we can't 'offer' a/c to another sector. Our primary strip display is the good old paper strips in plastic holders which we write on.
Were we to have to make a telephone call to the next sector to advise the hdg that each a/c is on (as 90% will be on a hdg given the number of a/c in such a small piece of airspace), then the operation would grind to a halt. Hence we simply ask you to report the hdg we have assigned you to the next sector.
In terms of it 'cluttering up the freq', well yes, I guess it's 2 words that in an ideal world we wouldn't have you saying but hey, we're not living in an ideal world.
To try and compare the UK ATC system to yours (I guess USA??) is slightly bizarre given the amount of airspace you get to play with
