I saw this a while ago: Myths of American Armor. TankFest Northwest 2015: An address on some of the common misconceptions about American armor in WW2 (The Chieftain (Real name Nicholas Moran) is Wargaming America's resident tanker and amateur historian. In addition to doing research for the tanks in the game). And wasn't 100% sure about his assessment of the Firefly in there. Something that has stood out to me as being often repeated was the way that the British used their Fireflys - "issued in the way of one per troop" - to quote (at around 20secs in) from here: Whilst this was not actually so for the 24th Lancers as "there was much debate as to how best to use these new weapons" (cf. page 61 of None Had Lances - The Story of the 24th Lancers) and who instead opted to "group three 17-pdrs together in one troop", and using them together rather than putting them at one per troop might have benefited them in the situation where the Germans were first targeting the Firefly, as at least then you might still have 2 other Firefly's relatively nearby, to lend assistance should they be needed, whereas if you only have one Firefly per troop and that Firefly is the first to be taken out the other tanks in the troop might be vulnerable and faced with less options there.