Hi Karen,
How much free running and when? How long is a piece of string? For the novice I understand your confusion, like everything in training a dog, let alone a HPR there is no one fits all solution. Even If you take the two extremes of dog, the huntaholic and the leg warmer, there will always be those that fit somewhere in between, and at different stages of their growing up these dogs can move one way or another.
It all boils down to reading your dog, and if you can't do it get along to someone who can ( always worth the petrol!) . If your dog has confidence and is happy to run a distance from you this is fine but it must always be under your control, at your chosen distance, let them go but be ready with the brakes once they stop checking in with you, or range to far. You must also start putting in its parameters of correct behaviour around game, checking chasing, encouraging correct use of the wind, etc. These will all help to instill in the dogs mind that they are hunting with you and you are leading the hunt rather than you are a passenger to the dogs self hunting. ( Remember all free running is hunting, its only a matter of efficiency)
If your dog lacks confidence and is reluctant to leave your side, leg warmers, these dogs are the ones you take a Valium put your whistle in your pocket and give them free range and allow them to get themselves wound up and excited around game without applying too much control, including chasing! this does not mean you do not train, especially the stop and recall, but you train these away from the hunting exercise. ( Free running on gamey ground)
One piece of advise, that may get me into hot water with the fairer sex ( but I'm always up for sharing a bath!) You may be good at multitasking, but you can not do it when your dog is free running! Once a dog is off the lead it must have your undivided attention, no mobile phone calls, no making a mental shopping lists, no wondering what your going to have for tea! The dog knows when your not focused on it, no matter how far away from you it is, and you will be guaranteed to miss a vital signal ( even if you don't know what it is!) And just to be balanced, men who are of course totally incapable of multitasking, no daydreaming of that nice Ferrari being driven by that well endowed lady you saw on the petrol forecourt! Imaginary shooting of those pigeons that flew over is acceptable, as you are supposed to be hunting with your dog!
So remember free running is not a right for the dog it is a privilege that has a purpose and a cost, and you have a responsibility to the free running dog to give it the attention and direction it requires. How much is all down to confidence, both in respect of the dog and your reading of the dog. There is nothing wrong in keeping a dog on a lead occasionally especially if your distracted or conditions for the dog to learn the right things rather than the wrong things are not favourable.
Incidentally, puppies and young dogs should always be hunted into a head wind, in this way they learn about scent and wind, and it becomes instilled into the dog to work across the wind ( Quartering). When the dog is older and is then presented with a non head wind it will automatically adjust its pattern to accommodate the wind, this will both help the dog find game and help you the handler read the conditions more accurately by reading the dog, remember this is a partnership were building.
Peter