TF2 and HT2 return this error "AppFramework : Unable to load module /mnt/raid/SteamLibrary/SteamApps/common/Team Fortress 2/bin/filesystem_steam.so" when installed on >2TB XFS file systems.
Made a few attempts, failed every time. Switched to EXT4 and it worked as intended. Tested on Fedora 20.
My mistake. This has already been fixed and reported elsewhere: ValveSoftware/Source-1-Games#1685