Being a born in (now a "bored out") I can earnestly say that I never learned a thing from the ministry stool. All I've ever seen are a bunch of people forced to go against all natural inclination, get on a stage in front of everyone and speak on a subject they know nothing, and could care less, about. The organizations one size fits all strikes again!
Everyone has different natural abilities, some just do not speak eloquently or simply have stage fright; forcing such one's to learn to be a public speakers is pointless. Even if you aren't fearful of having an audience, to be an effective public speaker you must first know how to properly speak your own language. This means understanding punctuation and the fact that when it is written it must also be spoken in such a manner, I highly doubt God meant the bible to be drawl and monotone. Next you must understand your material, if you don't, what right do you have trying to teach it to anyone else, get it straight first then present it. Finally you must convey yourself and your message in an appealing manner, to do so you must somewhat like or believe in your material or it's all a complete waste of time. The whole point is you are trying to convince your audience of something, if you don't believe they'll know it, if you're faking they'll see it and if you aren't enthusiastic they'll get bored and lose interest.
I never learned any of these things from the ministry stool.
I've got the gift of gab, but I learned to speak publicly because of my job. 15+ years of business management and retail sales taught me more than my entire JW experience ever could, something I love to rub in the smug stool oversneers face every time he gives me council on a talk.