I'm in two minds about this. On the one hand, it is a bit of a waste of time, because the guy already has the skills and knowledge necessary for the job. However, I'm inclined to support the decision that the guy should still get this degree, because at the end of the day anyone can lie about stuff like that on their CV (though with a chance of being caught, admittedly), but you can't lie quite as easily about having a degree which proves you have the knowledge and everything. And it'll be much more useful, therefore, for the guy when he tries to get a different job some years down the line and needs to prove to bosses that he has the knowledge and skills necessary. Most bosses nowadays will turn around and want proof that you have the right knowledge before hiring you, and a degree acts as that proof.
And I know what I'm talking about here, because my own father is in the same position. About two-and-a-half years ago, just after I go into university, my dad got laid off from his job as a contracts manager for a building company, where he'd been earning roughly £50K a year. He was on the dole, trying to find a new job, but eventually managed to get a less well-paying job with a much smaller company (though the same job and title, as a contracts manager, which is very high up in the firm). He hates it there and is trying to find a new job all the time, with a better company and higher pay, but for the moment he's stuck. Now, my dad happens to have a massive amount of skill at his job. He started as a carpenter when he finished school (with the most basic qualifications, I might add) and over 25 years has worked his way up through the construction industry. He owned his own small business as a decorator for a short while. He has a string of very high-profile projects to his name (including being contracted to work on the building of the glass roof in the main hall of the British Museum), and he's won tons of awards for his housing sites when at his former employer (both as a Site Manager, for Best Site and Best Site Manager, several years running, and as a Contracts Manager since then). Overall, he knows his way around the job and would be a major catch for any company (he's been headhunted several times from different companies in the past ten years, before he was made redundant).
That being said, he's now found out that despite all this, no major company will hire him without the sort of qualifications colleges and universities in the UK offer for the construction industry. He's had to start going to night classes at a local college and do a set of courses, mainly NVQs and BTECs, to 'learn' all the stuff he's known how to do for years. A lot of the stuff, as well, is stuff that doesn't even apply to his job (like various maths based courses, where he actually asked me for help seeing as I do a Maths BSc), but he still has to do it. All of this so he can get a better job and have a better chance than the wet-behind-the-ears graduates fresh out of university who've probably never held a bricklayer's trowel or a saw in their lives.
So yeah, to answer the OP's question, I reckon it's kind of pointless, but there are benefits too. The sad thing is those benefits shouldn't have to exist, because the experience should be enough in this case to justify the guy being given the job anyway without having to jump through hoops. Unfortunately, that's life, and we just have to learn to deal with it and move on...