This is nothing new.
I have found that since titles are thrown around so much in the industry I don't place a lot of value in them and use my eyes and brain instead to see what the line cook can do.
I have an issue as well.
If these guys really WERE Sous Chefs then they should have a lot of knowledge, comparably to the Chef they worked for.
The "bad habits" thing makes you wonder doesn't it?
On the other hand, it is quite possible that the former Sous knew they were not management material and simply wanted to cook.
I have hired people with former management skills and it's a crap shoot.
Some liked to micro-manage the line and some fit in quite well.
I think it depends, a sous chef who is use to doing about 80 covers a night is probably the equivalent or less of a lead line cook at a restaurant that does 300 or so.
Menu size, cuisine, changing course menu's, covers, all play into their actual experience.
The problem with newbies, is that when you get slammed in the weeds, they don't react as well under pressure.
I think the problem is that people mistake experience for skill. The two are separate. To many times I've seen people name drop restaurants they've worked at for whatever amount of time only to perform poorly.