They maintained the lift-n-lock keyboard for a while, but ultimately dropped it to get the size more under control. I have to agree with their decision, while it was a neat feature I didn't use it that often, and it came with a pretty massive weight/size penalty, especially when you wanted to use it as a tablet.

Ironically, one of my Thinkpads is a "thin at all costs" one - the X1 Carbon. Still has a solid selection of ports though.

Yeah I've owned 2 'modern' Thinkpads, and both have been well worth the premium. First one never had any issues, still works today, including the locking keyboard (OG Thinkpad Yoga). Second one did have an issue, but they overnight shipped a replacement motherboard to a tech who replaced it on-site the next day, for $0.

Combined they're nearly 20 years old and still trucking, which is amazing considering the abuse they've received. If Lenovo could figure out the whole stylus thing, I'd love to get a Thinkpad tablet/foldable.

Other doors and walls are not rated, though the construction of most walls isn't terribly different from a rated wall - a gyp studwall. Where you lose the rating is penetrations aren't protected, so it's easy for fire to bypass the assembly.

It's not that you run down the stairs so much as a controlled shuffle. The whole point of the fire rating is to give people time, so no need to rush and potentially hurt yourself.

Yeah, it can be a pain when the fire alarm goes off at 3am and you're 40 stories up, but ultimately all of this stuff exists because people died. Take advantage of all the things that make modern buildings safer.

In the US, high-rise fire stairs are sized based on occupancy, and rated for 2 hours of fire protection. They're also pressurized so that smoke doesn't get into them.

2x4 refers to the rough cut dimensions, so that's why. Modern studs are "finished 4 sides", which decreases the dimensions after rough cut.