[...] Wrong. As I explained above, if cl_interp_ratio/cl_updaterate is higher than cl_interp, the game resets cl_interp to cl_interp_ratio/cl_updaterate. Then it still gets the value from cl_interp. This can easily be verified by checking with the console and reading the code in the Source SDK.

[...] The game will not always get the value from cl_interp. It will ONLY get the value from cl_interp if cl_interp_ratio / cl_update rate is lower than cl_interp.

[...] What the wiki doesn't say is that the game will always get the interpolation from the cl_interp cvar. cl_interp_ratio just acts as a limiter for the cl_interp cvar, the cl_interp value will change automatically based on cl_interp_ratio (if too low). [...] That, too.

you can't change rates while alive

[...] What's there to abuse? I quote from source developers: This is the relation between snapshot rate and view interpolation delay is the following: interpolation period = max( cl_interp, cl_interp_ratio / cl_updaterate ) "Max(x,y)" means "whichever of these is higher". You can set cl_interp to 0 and still have a safe amount of interp. You can then increase cl_updaterate to decrease your interp period further, but don't exceed tickrate (66) or flood your connection with more data than it can handle.

[...] I think he might have meant "abuse" in a different way. Meaning that people use cl_interp 0 as a quick shortcut to set their interp to the correct value.

[...] What's there to abuse? I quote from source developers: This is the relation between snapshot rate and view interpolation delay is the following: interpolation period = max( cl_interp, cl_interp_ratio / cl_updaterate ) "Max(x,y)" means "whichever of these is higher". You can set cl_interp to 0 and still have a safe amount of interp. You can then increase cl_updaterate to decrease your interp period further, but don't exceed tickrate (66) or flood your connection with more data than it can handle.

People just "abuse" cl_interp 0 because the game sees that it's a bad value as it's lower than cl_interp_ratio/cl_updaterate, so it resets it to cl_interp_ratio/cl_updaterate.

Here's a complete explanation for entity interpolation in case you're the curious type https://developer.valvesoftware.com/wiki/Source_Multiplayer_Networking cl_interp literally pointless, because cl_interp_ratio already does it's job more safely and efficiently. Your current cl_interp 0.03 doesn't do anything, because your interp_ratio/updaterate already sets it to 2/66 which is bigger than 0.03 and already "optimal". I've heard vague rumors about setting cl_interp "0" causing it to default back to "0.1", but I can't confirm that. For safety, I would set it to something tiny but finite (anything smaller than 1/66 shouldn't do anything).