HD's reply may be valid in an approach environment.
Area control use 5 degree changes quite frequently because at higher level and higher speed it is more effective....larger turns may need corrections to remain in regulated airspace.
US-air and Transat have made similar comments in the last two weeks. Our cousins have no concept of the incredible density and complexity of UK airspace, nor the fact that we can only operate in corridors as and when permitted by the military, and a system of danger and restricted areas that seems designed to strangle any coherent traffic flow system.
I'll try a few non-heading options over the next few weeks.....based more on speed/vertical control......be interesting to see the result.