Yes, musical theatre is not my field, and I don't wish to engage in the ins and outs of the final casting, and its suitability (which I will leave to CCP experts!). But as regards the way the TV show *itself* was 'cast' - clearly, what they were looking for was contrast in look, human interest stories, a certain degree of ethnic preference, a smattering of underdogs/sob stories, and so on. Essentially, the show functions only as 50% a singing contest that individuals tune into to hear; the remaining 50% of the show (and virtually *all* of the news and media coverage) focuses exclusively on the 'drama', which is created on the basis of the personalities/ backgrounds that have been selected to take part. This is, basically, what conditions viewer reaction to performance (particularly because the public perception of what good musical theatre skils actually are is seriously lacking), so, the viewers end up rooting for certain performers because they grow conditioned to see them as 'such and such a type'. This much is obvious. The original auditions would have been concerned primarily with selecting those who would make the best television from amongst the applicants, which is what I think we said all along.
It is interesting, in my opinion, that there seems to have been some clear articulation by Lloyd Webber that he wanted Jessie to win, and that he was essentially unhappy with Jodie's success. Nonetheless, he acknowledged that she had been voted in by 'the public'. Consequently, he is assured of significant ticket sales in the near future but will, I have no doubt, for reasons of aesthetic preference, limit contracts to suit his own desired casting over the long run. The implication is clear that Lloyd Webber etc. did not feel that Jodie was ideal West End material themselves, but they appreciate that the win of an 'ordinary' woman, who was selected to take part because her story is one of struggle with weight problems, domestic issues, issues of age etc. that will hold resonance for thousands of 'ordinary' people up and down the country, is a guaranteed ticket seller. Jodie won, in other words, precisely *because* she is an undertrained talent. The story the public would always prefer to hear is that anyone can become famous overnight rather than spending years toiling anonymously in the vineyard for decades without money and/or recognition, regardless of actual skill. They sometimes feel insulted to realise someone has actually worked for years at a given profession, and not yet succeeded in it (which they frequently equate with a form of 'unfair advantage'). It's all based on totally faulty appraisals of what makes good or bad theatre, but Lloyd Webber etc., of course, know this full well - they justify it by veiling it under the rubric of 'popular voting'. As has been pointed out in another context, no one is risking the chance that the ensemble etc. are not fully trained and highly proficient - they'd be fools to - so, it's always one rule for the 'glamourous' star and another for the vital cogs that hold the show together!