Believe it or not, the Mountaineer's Route is easier and much more fun than the regular route in winter conditions. I summited via the regular route last April, right before the lottery season opened (check out my profile history for my trip report). It was a record snow year and it was full-on winter conditions at the time. In winter I'd argue that it is more dangerous than the Mountaineer's Route.
What makes it more dangerous is the John Muir trail section. In summer it's a sidewalk hike from above the switchbacks to the summit. In winter, the trail can be covered with snow. Last year my partners and I had to cross more than two dozen snow barriers including some as high as fifteen feet, through no-falls zones, in order to reach the summit. You're also further from help on the standard route, if something does go wrong.
Last edited by 123Zero; 02/20/20 12:47 AM.