It's safe to say that George R.R. Martin is not the world's most prodigious author. In the five years since his last book in the Song of Ice and Fire series — A Dance With Dragons — HBO has written, produced, and aired six full seasons of Game of Thrones. It's hard to blame the guy for the pace of his writing, with much of his time taken up by talk show appearances over the last few years, but a letter unearthed from the pages of a 1960s comic book might explain why Martin takes quite so long to write a novel — his meticulous research.

In the letter — posted to Imgur this week — a 16-year-old Martin chastises comic legends Stan Lee and Jack Kirby for a continuity error in their Fantastic Four series. "I regret to inform you that I found one flaw in this otherwise perfect masterpiece," Martin wrote in 1964, diagnosing a flaw that he says is "regrettably, very common" in Kirby and Lee's work. "When we last saw the Red Ghost in Fantastic Four #13 he was stuck on the moon being chased around by three super-powered apes livid with hatred and waving Mr. Fantastic's paralyzer ray at him. Now suddenly you bring him back in full control of his apes without one single word of explanation."

"He was stuck on the moon being chased by three super-powered apes."

Martin continues, complaining that Kirby and Lee have pulled the trick before. "This isn't the first time you've brought back a villain without properly explaining how. You did it when you revived the Puppet Master in Fantastic Four #14 after Reed had pronounced him dead in Fantastic Four #8." Martin closes his missive by wishing Lee luck in forthcoming books, but advises him not to pull any more returning villains out of his hat. "Next time, tell us how they remade the scene — o.k.?"

Assuming Martin's ascribing the same stringent background checks to his own cast list, the lengthy delays between books start to make sense. The Song of Ice and Fire series is full of hundreds of characters, each split over thousands of miles, and with generations of history governing their interactions with other houses, their peers, and their underlings. As much as a sensible author might want to retroactively tweak their back story to leave characters like Gendry on the moon being chased by angry apes with rayguns, Martin's meticulous mind wouldn't allow that, even in his teenage years.

On the plus side, the author does at least use the talents of his own super-fans now, meaning he doesn't have to sift through his own convoluted history on his own. Maybe we'll even get The Winds of Winter before Game of Thrones the show finishes for good?

LEARNING THE GAME OF THRONES THEME SONG ON A FUTURISTIC KEYBOARD