I'm familiar with the basic story from the Bible, although it's been a while since I read it. In particular, I remembered that Joseph's brothers throw him down a well and pretend he's been killed, because they're fed up with him, so they're basically the villains of the piece. However, in this performance they actually came across as quite sympathetic.
In "Dogbert's Clues for the Clueless" (p49), he offers this advice:
Sharing your dreams
Do not tell people what role they played in your dreams, no matter how meaningless it seemed to you.
Woman: "Dilbert, I had a fascinating dream about you last night. I dreamed it was a beautiful summer evening. The moon was full... You appeared as a field rodent. I crushed you with a big flat rock."
Dilbert (frowning): "Thanks for telling me."
If Joseph kept having dreams about his brothers all bowing down before him, he should really learn a bit of tact, and keep his big yap shut! Really, I blame Jacob (his father), since he was spoiling Joseph with special treatment.
As for the famous coat, it struck me that it's actually quite garish. Really, would you wear something like that in public? In fact, it reminds me of a jumper I had at school. One of the odd rules at CH was that you were only allowed to wear a navy blue V-neck jumper for the first three years. (You didn't have to wear a jumper at all, but if you wore one then that was the only acceptable design.) From the fourth year upwards, you were allowed to wear an "illegal jumper", as long as it wasn't visible under the Housey coat. So, just before the start of my fourth year, I chose a purple jumper with flecks of pretty much every other colour in it. In hindsight, it was quite revolting, but I liked it.
I wasn't expecting the performance to be funny, but there were some bits that really made me laugh (particularly involving the puppets), and lots of other scenes that left me sitting there with a big grin on my face. I think my favourite line was: "It takes a brave man to wrestle a goat."
I was also surprised at how revealing some of the costumes were! More generally, you shouldn't expect rigorous historical accuracy from this: the anachronisms become more obvious as the performance goes along. If you played Civilization II, and you liked the council of advisors (sadly missing from Civ III and Civ IV), then there will be something for you to enjoy in this musical too.
I didn't watch the BBC series where they auditioned for the lead role, but I think the guy they picked did a decent job, as did the rest of the cast. However, I'd say that the real star of the show was Jenna Lee James, playing the narrator; she has a very powerful voice. Speaking of the music, there was a bit of variety. I prefer the bouncy pop tunes: the first half had plenty of them, but the second half dragged a little bit. However, they saved the best until last, so there was a great finale.
When we left the theatre, there were lots of people queuing up outside. This seemed odd, since surely there wouldn't be another performance at 10pm? It turned out that they were all waiting to get autographs from the cast. My colleague said that we should have waited inside slightly longer, then pretended that we were actors too; that would have been quite funny.
All in all, it was a good evening. I personally wouldn't pay £50 for a ticket, but I'd be happy to watch it again if it comes round on the duty list.