> So they diversify his retirement with stocks in the companies they worked for.
It's better to have stock in 4-5 companies than in 1 (talk to Enron employees about that) but it is far better yet to have stock in 4000-5000 companies, if you are looking for diversification.
So, when you get the stock at below market prices, you should immediately be thinking how to diversify it.
I am not a financial planner, but I do manage my own portfolio.