How does series that were in 1990 have anything to do with test cricket today? The simple fact that England have improved is exactly that, fact.
When Fletcher took over England were effectively bottom of the test rankings, they are now 2nd. If that is not proof that in the test arena England have improved than I do not know what can be said to convince you.
I like to look at results within the last 2-3 years as a benchmark for a teams success, as if you got back further the teams are rarely the same as the teams 3 years down the line. It is afterall unfair to bracket a new look side with their past sides failings. At the most 5 years is a good indication.
End of the day, Englands results in the last 2 1/2 years are, unbeaten in all but their 2nd most recent series (up until then not just unbeaten but having won every single series), away on the subcontinent. That was a bad series in Pakistan (and I believe every team is allowed one bad series). Following on from that a highly credible draw in India regarding the circumstances is yet further signs that this England side is a very different proposition to ones from as far back as 1996 and 2001, even further back.
Afterall the Windies have pretty good records against everyone if you go back to 1990, yet there is no way that their side then can be compared to the current side, same is true of England although in the reverse.
In my eyes Englands performances in India in the test series lead me to believe that India could struggle the next time they are in England unless there are some changes, as I believe Pakistan and Sri Lanka will this summer.
Odi arena, they could be playing on the moon and still India would probably beat England, although a pitch with a bit of pace and bounce with the majority of the unavailable players available would at the least cause the Indian batsman a few more problems, and allow some of the English batsman to feel at home.
edit - to add, yes I do agree with you however than it would be difficult to seperate England and India as test teams, both have a lot of talent, and both are susceptible to the odd collapse. I do not however think performances 10 years ago are in anyway useful in gauging the various merits of the two sides. Why not use the fact that they just drew 1-1 to show that they are more or less even