Good point(s). In my opinion, deprecating an option should get a warning when it's used in one major version (let's say 3.6) and then be retired in the next version (let's say 3.7). For this to work, we'd need to also add some code to detect the use of any of the deprecated class expressions and print a warning like:
```
WARNING: Use of deprecated class SuSE. Use SUSE instead. This class will be removed in CFEngine 3.7+.
```

How does that sound?