By the time George R. R. Martin releases The Winds of Winter — the penultimate installment in the Song of Ice and Fire series — Winter may have come and gone on HBO’s Game of Thrones. His writing process is slower than a trip from The Wall to Dorne, but Martin’s friends have recently shed a little light on just why he’s so damn slow.

Elio García and Linda Antonsson began as Martin’s fans but evolved into his writing partners, as they co-authored the encyclopedia The World of Ice and Fire with him. Known to the fans as Elio & Linda, the two recently told INSIDER it comes down to two things: planning and Game of Thrones itself. As Linda explained to INSIDER:

As the books have become increasingly complicated, there have [also] been increasing demands on his time. With the attention from ‘Game of Thrones’ publicity [and] all these other things, it’s certainly true that he has a lot of irons in the fire. He’s very happy with the show and the showrunners and the popularity it has brought to the series,… At the same time I think there’s a little bit of ‘woulda coulda.’ Like if [HBO] just took a bit longer with this maybe he could have caught up.

Linda also spoke of his practice of not outlining, lest he lose interest in his own story. Although this might have hindered his speed, keep in mind that his original outline romantically linked Arya and Jon, so it might be worth Martin not having one.

According to Martin himself, he’s in the process of catching up, and will release the long-awaited penultimate book within the year. Maybe. Possibly.

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