I'm kind of surprised that after all these years TF2 and Source are still separate entities. Like, is there any TF2-only code in Source that only runs if TF2 is the current mod?
The Source engine powers more than just Team Fortress 2 so of course they'd be separate.
There might be some Team Fortress 2-specific stuff in the engine (certainly the GoldSource engine tweaks a couple of things based on which game is running) but I doubt it - the Source engine relies a lot more on expecting game code to implement a bunch of interfaces.
There might be some Team Fortress 2-specific stuff in the engine (certainly the GoldSource engine tweaks a couple of things based on which game is running) but I doubt it - the Source engine relies a lot more on expecting game code to implement a bunch of interfaces.