Of course not. But cargo cult interpretations have cropped up before (i.e. Shock and Dogged/NWI on 2-wound models). And the only mention of the use of Smoke Grenades not being an attack is that mention of "since it's not an attack...", more or less, which indicated that there was another passage that actually declares it as an attack. Which isn't present in the rules.... making it not rules. It's just that I could see CB going "Of course you can throw Nimbus grenades on friendlies/Civilians! It just creates a terrain zone. It's common sense!" and then not ruling on it or FAQ'ing it for 6 years.