@sersut  -
Thats right, we do not pass the interval & splay to the child process.
We pass the config_file and log_location.

The other params that we are passing to the child process are: log_level, chef_server_url, force_formatter and force_logger. 
If we do not pass the log_level, it may default to a value other that the one set on CLI. Eg - user may want debug messages but they will not get logged if we dont pass log_level. 
There may be a different chef_server_url set from CLI, which needs to be passed. 
force_formatter and force_logger are 2 logging related params which have a ref in the windows_service code, so I passed them to the child process too.