> Say I send a copy of a free-as-in-freedom game that I may or may not have modified in some way to a friend or on a forum, should I pay its author(s) for this?
Your friend would have to buy a copy of the original game from the author (or a reseller) before using your modified version of the game. You could even sell your mod to others, but they would also have to own a copy of the original software in order to use it since what you'd be selling is the modification, not the original software it depends on.
This is technically already legal, except most apps don't have the source code available for you to modify in the first place, and some companies try to abuse license terms to prevent it.
> How could I, for instance, commission someone to modify software if I want to change it when I don't have the skills to do so myself, in your definition of free software?
You'd just... do that? Same way you commission a mechanic to rotate the tires on your car. You'd have the source code and build tools. What's the problem exactly?
> Restricting how software is redistributed holds a great deal of power
I agree. I don't think authors of my version of Free Software should have control over how software is distributed except that new licenses have to be purchased from them. Once a license is sold, I don't think the author should have control over how that license is used or who it gets transferred to (except perhaps a modest limit on how frequently it can be transferred, to prevent shenanigans like third party floating license pools).
> developers can be paid not per copy, but per patch
I don't think this is very practical with Stallman's version of Free Software, because once you sell one copy of a patch that person can just turn around and sell it to others, undercutting you. So you'd have to price your patches at an absurdly high rate to recoup your costs. Effectively you'd be selling a personalized support contract, not actually selling software. This model sort of works in commercial contexts (hi Red Hat), but it's clearly not competitive with the proprietary software model. (Compare the market cap to giants like Microsoft, IBM, Oracle, etc.)
Your friend would have to buy a copy of the original game from the author (or a reseller) before using your modified version of the game. You could even sell your mod to others, but they would also have to own a copy of the original software in order to use it since what you'd be selling is the modification, not the original software it depends on.
This is technically already legal, except most apps don't have the source code available for you to modify in the first place, and some companies try to abuse license terms to prevent it.
> How could I, for instance, commission someone to modify software if I want to change it when I don't have the skills to do so myself, in your definition of free software?
You'd just... do that? Same way you commission a mechanic to rotate the tires on your car. You'd have the source code and build tools. What's the problem exactly?
> Restricting how software is redistributed holds a great deal of power
I agree. I don't think authors of my version of Free Software should have control over how software is distributed except that new licenses have to be purchased from them. Once a license is sold, I don't think the author should have control over how that license is used or who it gets transferred to (except perhaps a modest limit on how frequently it can be transferred, to prevent shenanigans like third party floating license pools).
> developers can be paid not per copy, but per patch
I don't think this is very practical with Stallman's version of Free Software, because once you sell one copy of a patch that person can just turn around and sell it to others, undercutting you. So you'd have to price your patches at an absurdly high rate to recoup your costs. Effectively you'd be selling a personalized support contract, not actually selling software. This model sort of works in commercial contexts (hi Red Hat), but it's clearly not competitive with the proprietary software model. (Compare the market cap to giants like Microsoft, IBM, Oracle, etc.)