However, if the player doesn't have episode 1 or 2, they won't get its shared models/textures.
Only the HL2 textures/models are included with any source game.
I could very well be wrong (I speak more from a reverse-engineering than a testing standpoint) but even if the player has Ep1 or Ep2 installed, neither have resources on the search-path for TF2 so TF2 wouldn't be able to find them and you'd get checkerboards.
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