What I mean is going by your stats you have an immense level of fitness. People like me that did pretty much nothing until starting to ride can notice a massive difference in their fitness levels after even a couple of weeks off.
I was just the same when I started, but as the article said (which I think backs up my point) it takes time, I only started cycling seriously in June 2012 so those breaks in the first 6 months would tell, it does fall off but not at the rate you think, look at it this way take your first ever ride then compare that with a ride having taken a few weeks of, I bet on the whole that ride after the break is better than your first ride, its took me nearly three months to get back to where I was a 10 months ago after not riding s much over the winter, but I rode most weeks at least once through the winter, not far 92 miles in Feb @13.98mph.
I hated hills when I started, not over keen on the killer ones even now, not that there are any really close, just some short sharp ones 150ft in 1/2 mile or so, it took me six months to do this one
http://app.strava.com/segments/3804327
and from this you can see how slow I was, I cant tell you what gear but probably 28x28 or something.
I do the same climb coming from another road so I have done it more than 6 times, and you can see I wasn't that quick on it last time, you also spend as much time climbing out of the potholes as you do climbing there are that many, thats part of the reason I don't go down it.
Its took me a long time to get where I am, a lot miles in all weathers, when I started I couldn't do a local 10 mile loop without stopping 3 times at least, these I can do 50Km like last night, but usually I stop after 40Km or so and have a cig.
There are many newbies than come on here and blow my stats away in terms of speed and endurance, we are all different, but once you get some basic core fitness unless you totally give up you will retain some of it.