While I use Linux daily, I don't use it heavily and I do not consider myself expert in its internals. I have an obsolete Debian installation on obsolete hardware. I use it almost everyday to quickly test code for portability, but I have not installed a Linux distribution in 7 years (discounting test driving the occasional livecd).
My linux machine uses three hard disk partitions: /, /home, and swap. Admittedly, that's not quite the one large partition scenario I mentioned in my previous post, but it's close. Most disk activity is confined to the root partition. There's not much going on in /home, aside from creating a few files a day, and having the shell write to its history file. I don't use X, just a the virtual text consoles. The machine never swaps (I'd know if it was thrashing). However, the system startup scripts start mysqld, lighttpd, memcached, and php. They generate quite a bit of activity on the root partition (/var mostly).
At least several times a month, in a hurry I force a hard shutdown (it's 15 yr old hardware). At other times, adverse weather causes a reboot (brown out without UPS). Still, in 7 years, the machine has never failed to reboot (although, obviously, it may have to fsck).
I also do the same with a Windows XP laptop. Never had any issues rebooting or losing data (after having closed all documents and apps except the web browser with its session management).
Perhaps I've been uncommonly lucky. Which, I may be. In 25 years, I've never experienced a personal hard drive failure <knock on wood>.
I will continue to tempt the fates until they bite me.
Regards,
Alister