I didn't argue anything about asking for permissions. Some how you extracted that. I already know most mod authors just plain wont give it. That is not the issue. The issue is that mod authors do not follow good policy for releasing mods. I.E when you update a mod you should be leaving a link to all of your old versions. GregTech is especially bad about this as is SoulShards and Forestry. over the weekend the file for even the current Secret Rooms wasn't available to anyone.
I constantly have players that cannot get the correct version for the server because of this issue. A private pack would allow me to fix that but if don't have the option of adding what I need in the pack without asking for permissions I am not going to get the feature is worthless. That is much less a opinion and more of a fact.
In the mean time I have no other option but to link the currently installed version via dropbox in order for people to play. Mod authors don't' seem to be concerned about this issue so I have to solve it myself. When I heard about Private pack I though this might be a solution finally. Apparently it's not.
Really? Not arguing?
If this is indeed the case, then this feature is 100% a waste of time and no further development should be spent on it. --snip--
That's opinion, not any fact content except it being your opinion. It's arguing you think the feature is a waste of time and that would be a fact so there's nothing to extract from there. So batting 0 for 2. What's up next?
Right, permissions still. It's not hard to get mod author permissions; most that want their mods distributed in a mod pack simply ask for a post or PM at Minecraft Forums so it's not exactly rocket science. If they don't make available a way to get permission chances are they do not want you distributing their mod. Period. End of story. There is no "work around" for this; it's courtesy and respect, as I said before. By distributing the mods without permission, you're just causing more problems.
Need an example? Tekkit started as a private mod pack made by and for some folks on SomethingAwful; somehow the pack got out, made popular by some let's play videos, and then all hell broke loose in the mod community. A lot of people are still butt hurt about the whole incident (as evidenced by a lot of mod authors terms of use). That is not opinion, it's 100% fact. That is why FTB requires permissions now, to avoid that from happening again. It's also why many mod authors are working well with FTB's team. If you choose the "work around" the permission requirement, you're just setting a lot of people up for a headache later down the line.... maybe not tomorrow or next week, but it will happen.
As for the version issue, well, it appears FTB caches the mods on CreeperHost to avoid eating all the bandwith/resources of the mod authors. Chances are if you want your mod pack to stay frozen at a particular version, it should be possible (of course, pending the mod's terms of use...). I'm going to flag this post to try and get some clarification on how that would work for private mod packs...
Of course, going to mention this again since evidently it's hard to comprehend;
It's not hard to get permission for mods that want to be distributed. Distributing the mods without permission is a very bad idea, regardless if it's for a 'private' mod pack or not. Respect the mod authors wishes; if they don't want it distributed, don't. If they just want a shout out or quick contact post, take the 5 minutes.