The Legal Expert: When is a divorce lawyer an "expert"

Our friends over at www.bedroom-to-courtroom.blogspot.com had an absolute seizure the other day when some guy wrote up some articles on Huffpost Divorce, calling himself a “legal expert.” The admin, Terri Weiss, got “angry” about it and she basically called him out since he only has been practicing  about five years and he also has NOT been practicing in matrimonial law. Rather, much of his practice has been in corporate law. It begs the question, though, when can an attorney call him or herself an “expert” in divorce law? I mean, lately, I’ve taken to calling myself a marriage expert, even though I’ve never been married. Ok. Shut up. You don’t have to laugh that hard. I am a marriage expert and yes, I became one by osmosis, and who is to tell me that my marriage advice is not sound and sensible and appropriate? Who is to say I am not an expert? Just because I may not have a bunch of papers on my wall that says I majored in marriage counseling, doesn’t mean I don’t know what I’m talking about. Today, I even did a post on the Sexy Sunday Morning Breakfasts and how it can save your marriage. This is good stuff! This is expert advice! And I did not major in marriage counseling.

So my question to Terri is, how long does this poor guy have to practice in order to call himself a divorce expert? Or to be given the honor of being called an attorney with expertise in matrimonial law?
Speaking of which, why do divorce lawyers have such a bad reputation? I was talking to  this guy the other day and he asked me what I did for a living and I said I was a  lawyer (didn’t get to the divorce part) and he blurted “oh, you’re one of those crooks! But I won’t hold it againist you.” And I thought, “I don’t wanna be a lawyer anymore. I think I want to be re-incarnated as a barefoot, blogger housewife who dispenses ‘expert’ unsolicited marriage advice.” That is so much more fun than anything else I’ve ever done. And I bet you nobody will call me a crook or balk when I call myself an “expert.”
But, yea. I need to find out how long does it take for a lawyer to become a “divorce expert.” And is it just a function  of the amount of time that lawyer practiced? Or are there other requirements? Memberships in certain organizations? Types of clients represented? Success rate (how many times did your client get cremed versus how many times did you creme the other side) and stuff like that? That is, my question is, how does an attorney become an “expert” in divorce and matrimonial law?