I'm 90% sure that this would not have happened if the pilots of the A10 were full-time air force servicemen.
The thing with reservists (weekend warriors), they have nowhere near the experience a full-time serviceman of equal length of commision (these were officers remember), and with that comes the unfamiliarity of allied vehicles. The don't recognise the profile of British tanks, simply because they aren't trained to recognise them.
That article didn't mention that the same British patrol, some hours earlier had passed a couple of Marines on the road, had stopped to discuss whatever, common procedure, but when the British Officer dismounted from his Scimitar, one marine said "Gee guys! Where'd u get the Iraqi tanks?" The British officer was in disbelief, and had to convince the marines that these were infact British Armoured Recon vehicles.
Now I'm not sure if those marines were reservists, but if they weren't, and they didn't know what Scimitars looked like, then how the hell are some yankie flyboys who are overexcited and just want to be heroes on their tour of duty going to tell the difference.
I have a fair idea of most US army vehicles that they use, and could recognise/identify each from a simple silouette profile, and I'm not even in the British Army (not till September, when I goto Sandhurst, Infantry Officer f t w!). US Marines are drones, they only know what they are taught, and they are not taught about British vehicles, and from this story, the same conclusion can be drawn of the USAF.