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Jonathan Siegrist Repeats ‘Flex Luthor,’ Skeptical of 5.15b Upgrade.

Siegrist has an encyclopedic familiarity with America’s hardest routes; he’s skeptical about the recent upgrade to 5.15b.

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When Jonathan Siegrist first visited the Fortress of Solitude in 2010, the crag had largely been forgotten. “Nobody was going up there. The only partner I could get consistently was my dad.” He was working on Kryptonite back then, which eventually became his first 5.14d, and during the process he occasionally glanced over at its neighbor, Flex Luthor, which had been established by Tommy Caldwell in 2003 and was America’s first proposed 5.15. “I was very intimidated,” Siegrist said. “The route had so much mystery around it. I mean Kryptonite had at least been repeated a couple of times,  [but] to think that there was something harder.…”

Even after he claimed Kryptonite’s fourth ascent, Siegrist didn’t try Flex Luthor. The Fortress of Solitude is not an easy place to have a project; the crag is something of a solar collector, baking hot even on cold days and seeping through much of the spring; and the grueling approach, at least when compared to non-approaches at nearby Rifle, makes it tough to secure climbing partners. So Siegrist turned his gaze elsewhere, and eventually moved away from Colorado (he’s now based in Vegas).

Meanwhile the route gained a reputation for, well, bad rock—thanks in part to the fact that Tommy Caldwell, who’d equipped the route, had done essentially no cleaning by modern standards.

Back in the late 1990s and early 2000s, when Caldwell was spearheading development at the Fortress of Solitude, chipping was a major part of the ethics narrative in the United States. Places like Mount Charleston and Mount Potosi, both near Las Vegas, had been central to the sport climbing scene in the early 1990s only to be scrubbed from the map, so to speak, thanks to the excessive chipping taking place there. “Developers like Tommy were trying to write a different narrative,” Siegrist notes. “They were doing no cleaning. Tommy’s ethos back then was that he would only use a toothbrush and a nut tool when cleaning the routes. No glue. No excessive chossaneering. Basically putting up sport routes in alpine style.” 

This minimalist ethic led to mixed results at the Fortress. The rock on Kryptonite, Siegrist says, is quite solid, so Tommy’s approach yielded good results. “But on Flex the rock is not nearly as good. Tommy found a path and made it work, but when subsequent suitors came to try the route, things were breaking, and that deterred them from continuing to try it. I remember that Dave Graham tried it [and gave up]. I remember Sam Elias put in a lot of work trying to clean it up. I even heard a rumor that Alex Megos tried it, decided that it was choss, and decided not to try anymore.”

Then, in 2020, Matty Hong gave the route a go and found himself surprised by how solid the rock on the second half of the climb was. He cleaned it up and eventually sent it last October—proposing an upgrade to 5.15b and effectively propelling the route back on Siegrist’s radar. 

“Seeing Matty do it, and seeing video of the route, was crazy inspirational,” Siegrist says. “It made it seem like way more of a climb than just this story.”

Flex Luthor Back to 5.15a?

Siegrist made quick work of the route, sending on Halloween after some six days of effort over several weeks. For him, it breaks down to five or so bolts of 5.13 climbing on the route’s worst rock. (“It’s not too bad to do 5.10 climbing when the rock is really bad, but when you actually have to do hard moves, it adds a sense of tenuousness.”) After that, you enter the crux, which is where the rock gets better. For Siegrist this section consists of a six- or seven-move V10 or V11, though Hong thought it was more like V12.

“It’s really awesome movement,” Siegrist said. “I did it more or less the same way as Matty. You do this huge move to a really cool pinch, then move your body around the pinch. Imagine a protractor: The pinch is the center, and your left hand basically never leaves it, but your body starts on the left and basically revolves all the way around. … I’m really grateful to Matty and Carlo [Traversi] for unlocking that sequence. They’re boulderers, and I think they’re able to think outside the box a bit more, using faraway toehooks and other crazy movement. If I were there alone, without anyone giving me info, I may have eventually found the sequence, but it would have taken me a really long time.”

After the crux, some “pretty taxing” 5.13 climbing leads to a jug rest, which is followed by “a solid 5.14a” to the top.

Jonathan Siegrist crimping hard on Flex Luthor
(Photo: Cameron Maier)

As far as the grade goes, Siegrist says that he doesn’t consider Flex Luthor’s recent upgrade (to 5.15b) an accurate representation of his experiences.

“There are two main compasses that I try to use for grades,” he said. “One is time invested, and two is effort expenditure. I gave it quite a bit of thought. I do think that my climbing is pretty good right now. But for me, six days is remarkably faster than any other 9b [5.15b] that I’ve done. I was one-hanging the route on my third day. And while I did put in a huge fight when I sent it, to me it didn’t quite feel like the amount of effort I would expect to put in—in the moment—on a 9b. When I think about it compared to routes like Stoking the Fire or Jumbo Love or even Event Horizon, for me, there’s just no comparison. It feels like a totally different category. … But who knows? Maybe I got really lucky. Maybe I’m in great shape. If years from now it’s consensus 9b, I’ll be super psyched about that. … But for me it felt like 9a+ [5.15a] is the best grade.”

How many more ascents will Flex Luthor allow?

As far as the route’s condition goes, Siegrist said that parts of it are still “going to change.”

 “For now it’s totally climbable. It’s not like things are breaking off every time you climb on it. But if a modern developer was putting up the route, it would have 20 glued holds. Three quarters of the route is on great rock and is not going to change. But the first few bolts will. … It’s unfortunate, because while I think it’s cool to preserve the history of the route, the fact that it still has some of its slightly adventurous alpine-y character from when Tommy did it—and I’m certainly not going to be the one to go in and do some heavy-handed gluing—the route will gradually deteriorate [without it]. I just wonder how many more ascents it will allow before that happens. I mean, the two most important holds on the route have already broken off and been glued back on.”

Holding space 

Flex Luthor caps another ridiculously successful year for Siegrist—he’s done six 5.15s—but he’s not much of a celebrator. When I spoke with him after the send, he said that he was focusing on “holding space” for “the version of myself who didn’t send.”

“It’s just a way of remembering that there are so many outcomes, and sending is one of them, but it’s not always the one that we get. And I have lived through so many different outcomes. There are times when it works out perfectly. But there are times when it’s the last day, and the last try, and the weather is perfect, and you just don’t do it. So I just try to remember all of those things. I never want to get too obsessed with the success part. Instead, I try to hold space for the version of myself who didn’t send. Because that’s going to be me in the future. I like to remember that that’s the way that life can go too.”

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