The SAS tell me that the 'black line' snail trail is the worst of all...

Yes, looking back at what had happened at SCHIPOL airport with TOMLINSON for example...he had taken me along (as I was normally taken along upon this 'ops') to scan a wide area - to see if anybody was exhibiting what I used to call 'negative' energy'...a moving cloud of dark energy...the whole person was like a dark SHADOW amongst the others in the crowds...and moving at a rapid pace...a microchipped slave in DELTA alter...assassin alter...I could see this type of 'energy' in 'grasse'...and acted as an early warning system for whoever I was supposed to be protecting...

...and I would guess that the equipment that the SAS are now using...is a far more sophisticated version of the above...