There is a modicum of sense in what mr slip and turn says. We used to do compressor washes at Gatwick on the DC10s in the 70's and this was well before the H&S people had bite. Every wing engine wash was done with a harness on and anchored to the faithful Douglas push back tug. This however was a set and well rehearsed procedure where the harness was a necessity. Even now I shiver at the power of the fan, would suck a pen out of the pocket no problem. Even worse was trimming the JT3D with the thing running, now that's just plain daft these days. I agree that many engine runs require the headset guy to be free to move about but now when I run ANY aircraft above idle power, the blokes are at the front windows where we can see them. Sad day indeed, keep safe . . . . .