John,
When did the BritishForces ever keep "anything" quiet, especially if it was light years ahead of the competition. There will always be a nucleus of leaders /designers/manufacturers, who want everyone to know everything, and nothing, but ensure the share price of the relevant company stays high!!
I watched a chap in Iraq in 2013 run across a road he simply disappeared as he mounted a U.S tank and only reappeared in a cloud of smoke which revealed the "cloak" so to speak. It was amazing, and not believeable unless you saw it.
Thats when they declared they had something that actually worked. It was a combination of the right camouflage clothing in the built up area in very bright sunlight. It was the smoke that gave it away and allowed the video person to capture it on film.
Fast forward to 4:30 and see for yourself