It's referring to the TODO on L427:
```
    // TODO(harvey): We might be able to reuse the QB passed into this method ...
```
Right now we're using the Hive QB from getParseContext.getQB to set fields in the QueryBlock that's used in the rest of SharkSemanticAnalyzer. But we might be able to just maintain one QueryBlock if Hive parent methods (mainly, super.analyzeInternal()) are called in a different sequence...