IMHO it is not up to ATC to instruct you to keep 10m/20m/100m from another a/c on the ground. It's your responsibility not to crunch another one. Coming onto stand, even self manoeuvring ones, the wing tip clearances are <10m. You follow the yellow line and use Mk.1 eyeball to ensure safe clearance: not just blindly follow yellow line. You assess what's in front of you and within the area you are going to place your a/c and act accordingly. Consider how close the wing tip gets to 'turn out stands' and the neighbouring a/c. Hopefully there is a wing marshaller, but not always. You manoeuvre starts with faith, then correct technique, then care. No ATC.