Ok I know it's in the documentation that all methods within the Position class require the Position permission, but I think what you mainly want to avoid when the Position permission is not on that you won't be able to do enableLocationEvents and/or getInfo (although you could just leave the latter return null)
I don't see a reason to prevent to call the parse method call or the Location constructor
Code to reproduce, add this test method to a datafield project:
(:test)
function verifyDistanceCalculation(logger) {
var locString = "51.5, 0";
var location1 = Position.parse(locString, Position.GEO_DEG);
/**var location1 = new Position.Location(
{
:latitude => 51.5,
:longitude => 0,
:format => :degrees
}*/
return true;
}