Lets not forget dedication and patience is a type of skill as well.
As it turns out MP players don't seem to account the fact that SP player also are challenged and have to overcome problems.

Jaker allegendly spent 80+ hours on a single replay. Being able to dedicate that much time to a single task isn't easy at all, especially when you regularly have to scrap several hours of work because it didn't turn out the exact way you wanted it to.
Theoretically a monkey could write shakespear, as Larfen pointed out. With enough luck hitting the right buttons anything could write theatre, even a branch in the wind.
The chance of a treebranch hitting the right letters on a keyboard for it to form an act is abysmally small though and statistically it would take millions of years of scraping documents for this to actually occur(no source, just making numbers up).
However, if I were to attempt a shakespear quality text I'd likely be able to do it. Sure it would take me several years probably but eventually the result would be fantastic.
Shakespear himself however would be able to humiliate my efforts by writing a similair quality text in what? 0,01 percent of the time?

To round this up, make an extremely high quality replay takes a lot of time. The more skilled you are at the game the less time it will take. And ingame skill can of course be improved.