The point is that England are okay. They're not great, none of the Northern Hemisphere teams are, but they're not shocking either. The media tends to take one extreme or the other.
I haven't heard any media outlets in Britain call England a great side. People are just praising England for what was their best performance in many years, and you know what, it was.
I can't find one media source saying England are a great side. I've read plenty saying they have the capacity to be a great side. And those media outlets have every justification to make those comments. I'm talking about publications like The Times, which is horrendous in it's British bias.
Losing in Ireland doesn't make you a dreadful side, nor does beating France at home make you a great one. But that's how people tend to react. Nothing at you in particular, but it's what annoys us about the "bandwagon effect".
Losing in Ireland when Ireland play they way they played was disgraceful. That was the worst game of rugby I've seen since a game between Australia and South Africa in 2006. Ireland was dreadful. The quality of rugby was so poor that any other major country in the world - Scotland, France, Wales, and the superpowers - would have won easily.
England were rightfully lambasted by the press for that game. Considering England have been playing poor rugby for many years (don't let the world cup fool you), I'd say that loss did make them a dreadful side 'at the time'.
I don't know what the exact criteria is for what makes a great side. Certainly one win isn't it. To my mind, the way England played for years prior to the game against Ireland, and the way the performed against Ireland means they were 'dreadful'.
As for what makes them a great side. I suppose they'll have to string a few better performances together of the same quality to be called 'great'. I certainly don't think they're great and haven't found one renowned rugby writer in England say they're great. All I've read was that they have potential to be great, and their performance justifies that comment...