If you are looking into using a properties file to avoid having to recompile/deploy every time you want to tweak a setting, I would suggest taking a look at 254's Constant implementation from 2013.
ConstantBase
Constants
It's a pretty straight forward implementation. Default values for all variables are stored in the Constants class. When an instance of this class is created (from robotInit() would be a good idea), it will go out and look for a file called Constants.txt. It will read in the key value pairs defined in the txt file. For each key/value pair in the file, it will search the list of known keys for a match. If it finds a matching key, it will overwrite the value specified.
Your Constants.txt file only needs to define values for keys you would like to override the default of.
I integrated the ConstantBase class into my team's code last night, haven't had a chance to deploy the code yet, but we will likely use this on our 2014 robot.