Former world champion blindfolded speedcuber, Tom Nelson, recently completed a 10 year project setting the world record for longest delayed 3x3 blindfolded solve. Tom Nelson won the 5x5 blindfolded event at the World Championships in Paris in 2017 but has not been cubing much in recent years and has focused more on animation videos, however, he completed the challenge he set for himself all the way back in 2015.

In 2015, he scrambled a cube and memorized the cycle of piece swaps required to solve it blindfolded, he then sealed it in a box, making sure to clearly mark which side was the top and front, with the plan to solve it blindfolded 10 years later.  In the video he explained how he would review the memorization about once a week on average but would occasionally forget about it for a month or two. At the end of the video he is successful in solving the cube blindfolded after not seeing it for 10 whole years!

In the video he also does a pretty good job at explaining how blindfolded speedcubing works and how he converts the letter pairs into words and places them in a room on a TV show that he liked, I wonder if he will ever forget the memorization that was required to solve the cube even if he will never need it again.