The Witcher 2: Assassins of Kings Interview

IGN's The Witcher Vault has conjured up an interview with CD Projekt RED's Tomasz Gop and Mateusz Kanik, and this time they quiz the developers about the expanded alchemy system in The Witcher 2: Assassins of Kings. Some pretty good info in here:
WV: How easy is it to get ingredients in the Witcher 2? Can you gather items from the get-go, or do you have to have a skill developed as in the Witcher 1 to even harvest the plants? We already know there's one ability that grants more harvested ingredient per single harvesting, anything else?

Tomasz Gop: There're three factors here. First, as you have said, there's a skill that increases the amount or the chance to obtain more of an ingredient in a single harvesting. For example, some plants can be looted twice in a row. In addition, many of the plants regrow...

WV: As in the Witcher 1?

Tomasz Gop: Yes. It takes them about 20 minutes real-time to become ready for the next harvest by default. But there's also a very special gift for alchemists in one of our launch-day DLCs attached to certain game editions. As far as I recall, those contain unique gloves and some herbs. Those gloves, for instance, can also influence the way you collect herbs - you can collect more ingredients at once. In addition, you can boost random chance to get the most valuable ingredients by gathering knowledge about monsters. Oh, and there's also that Mysterious Merchant you get when you order some of the Premium and Collector's Editions. This guy has also some interesting alchemy-related items to sell.

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WV: All right, one final question. What - speaking realistically - can Geralt the master-brewer can achieve in and out of combat using naught but his alchemy? We know that Signs can be used outside of combat (e.g. Axii) in order to persuade or influence someone. Within combat there's a ton of Sign- and Weapon-related abilities that make Swordsmen and Sign-masters particularly powerful warriors... so what can an alchemist do?

Tomasz Gop: Ok, let's shortly show how social skills work. Those are the four innate abilities that grow with each use, like Intimidation or Persuasion. They're developed independently. They're not tied to your skills within skill trees. Using Axii to appease the person you're talking to can succeed or fail, and the more you've done it successfully, the greater the odds of success next time. As far as I recall, it takes about 2 or 3 successful attempts to get the highest odds of succeeding when trying e.g. persuasion dialogue option. So it's not tied to any profession to begin with -- thus alchemists neither gain nor lose anything in terms of social influence.