Glad the hiker got out okay, other seasoned hikers, at least one who I've hiked with from here also got lost on Greenleaf above treeline, he went down the southern(ish) drainage. As Chris mentioned, in poor visibility, the cairns blend in as while Lafayette is not as broad as Washington, the trail isn't as obvious as the C-Path in many spots.
The mistake was made leaving treeline or the hut and not noticing the changing conditions. I'd question why continue up in conditions that were rapidly going downhill (If not rapid, he failed to recognize them during a longer period of time & from the description, he's been up there often) to see a sunrise that was going to be virtually non-existent. If he is as experienced as he says, he, like many of us, have taken dozens of pictures of gray clouds with a few rocks and visibility of 30-100 feet. (The 100 footers have a little bit of rime or snow covered scrub sometimes or rime on a summit sign)
In the last several years, Lafayette has had more than it's share of rescues, it seems that people think that since it's not a Presidential, the risk is much lower. That is not the case.
I wouldn't classify Pierce with the rest or the Presidentials, in fact its a decent place to go and pop your head out of the trees in poor weather and get back quickly into the trees. (I'd put Garfield, Liberty, Indian Head, Martha, Tom, Jackson, North Hancock and Tecumseh on that list also although some of those just have an open partial view and you have other navigational issues depending on ice, snow depth and water crossings)
The other thing that people rarely brag about are trips that do not go as planned. I've learned far more on these trips than the ones that provided great pictures. I love my Half Dome Sunrise pics from Sentinel Dome but it was a short hike near dawn after driving up to Washburn Point for Pre-sunrise pics. I learned much more on a cold North Twin trip where I made the summit however, the idea of a protected trip in bad weather along the ridge did not work out when the 6-8 foot trees had 4-6 feet of snow around them. (My knees had protection from the wind, in summer it's a dense green wind block.)
I'm very happy not to be on Facebook, (Rant stopped in midsentence & deleted....
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