Ok, however the whole force was low level about 3 years before TFR started to come in.
TFR was not the magic bullet. It had a non-steerable antenna +/- 3.5 deg. Any drift over that meant you could happily TFR into a hill or side of a valley. The H2S was essential as a backup.
At least on war sorties there were not many hills or valleys and the higher speed meant smaller drift angles.