It's worse than having to parse a matching bracket, because any context where you have an item defined via nested brackets is going to be a subset of this use case. But yes, that doesn't mean you couldn't do some theoretical eager processing, but it's going to be context dependent. For example, consider a Cargo.toml file, where we've processed the `features` key for a given dependency. Is it safe to begin compiling that dependency with the given set of features before we finish parsing the file? No, because there might be a `default-features=false` key that applies to this dependency later in the file. In a format where tables weren't allowed to be split, the mere act of parsing a single, self-contained dependency entry would be enough to know for certain that no such `default-features` key exists. Not all potential keys are going to require this sort of consideration, but it could be a footgun depending on the semantics of your schema.