Yesterday, I did a one-on-one interview with former Google spam fighter, Murat Yatagan (@muratyatagan), on Google+. Murat hasn't worked at Google in about a year, but he was very involved in spam fighting and webmaster outreach, now he works as an SEO consultant at semtr.com.
He said at the 32:55 mark in our interview, that Googlers who are in webmaster outreach, like he was and like John Mueller, Gary Illyes and others do get PR training. He said:
When I talked about my passions with my manager, that I want to become an integral part of the outreach team he sent me to a training and the training was given by PR people. So I get to learn how to talk about like a company, like on behalf of the company in concrete measures. But this changed in a bit more in time. So like I had I got strict guidelines but not to say this, not to say that, not to touch this question. If you get this question just ramble up and give back but after a while you become more vocal.
He goes on to explain the training was done every few months to every six months or so. But as time went on, Google got more relaxed about it. While some folks like Gary Illyes may say more, folks like John Mueller say less, because it is about how they like to answer.
Murat actually spent almost 8 minutes answering the question, so it is interesting to watch, here is the video embed:
Forum discussion at Google+.