Yes the 4 GB patcher works and is brilliant for older applications that were never made Large Address Aware (LAA), but it is unnecessary for TS3. This is something EA eventually got right as the EPs were rolling out, with Patch 1.17 back when Late Night came out TS3 will reach for and use up to just short of 4 GB of RAM on its own, if the RAM is available to it. The patch is not needed, any posts that say it is are I am afraid very outdated or just mistaken -- or the players are playing an unpatched disc installed game with no EPs beyond the first two. The actual upper limit on RAM usage for practical reasons though is ~3.7 GB no matter how it comes to happen. One single microsecond long spike above that and the game will crash or Error12 upon trying to save, which is just as bad.
To be clear, this is on Windows. The Mac version of the game still has a 2 GB RAM limit for other reasons and that cannot be fixed with any kind of patch, unfortunately.
