Does someone know how far you have to progress before you can use this "jump potion" and how it works?
  1. Does it only work after you unlocked the airships?
  2. Does it only work for one class/job on a character?
  3. Does it boost your level to...lets say 60?
  4. Does it complete your class and job quests?
  5. Does it boost your story completion to the beginn of 4.0?
  6. Does it give you items/gil/something you can progress further into the next expansion?
  7. Does it lower the skill of the player who uses it?
And this are the answers i have found for me:
  1. No one knows by now, but likely from a look on the chinese version.
  2. Likely from the PoV to bring a Char just to the beginning of the expansion.
  3. Most likely, because you should be able to enter the expansion and progress further from there.
  4. Most likely, some skills are to valuable for further progression to make differences between different jobs.
  5. Most likely, because you should be able to enter the expansion and progress further from there.
  6. Most likely, because you should be able to enter the expansion. and progress further from there.
  7. Most likely not, because a player who wants to learn his class/job will learn and a player wo refuses to learn wont learn it even with the MSQ and besides nothing in the MSQ teaches you anything for your class/job besides 50% of them are annoying fetch quests and you get some pactice for your class/job by running dungeons and trials, but we see it now that this doesn't really help if you meet players who have no idea how to play their job in experte roulette. Learning is a process and includes doing something repeatedly, getting advice, reading guides, incorporating new knowledge into my own and practicing. Just because a player used a "jump potion" doesn't make him less skilled then every other new player, he just have to manage the flood of skills instead of getting one after the other, but for this they will probably implement the "intermediate hall" and make them mandatory at least for ever "jump potion" user.

A "jump potion" is like a ferry over a huge river, you can swim or you pay the ferryman to cross over with you.
I don't get it why people are against it, at some point they have to come. if SE keeps the current model of story progression we won't see any new players in 2 to 3 expansions, cause they have to work through weeks or months of MSQ just to get to the current content.