why does it take the best part of a year and £1000 to gain some IR exams?
It doesn't have to take anything like a year. The notional study time is 200hrs, of which 20hrs have to be done in the classroom (unless you are a conversion candidate). The 180hrs of self-study is about 25hrs on average for each of the 7 papers. You can do it in much less than that. I suspect that the difference is people who book themselves into the exams, say 2months from now, will crack on and do it. If one waits to book the exams until you're ready it can easily drag on. I've been sitting on the book and software for an FAA exam since last November, just haven't got around to it.
The £1000 is an artefact of both the tiny number of people doing the IR only, and the JAA requirement for an approved course. We are very lucky that 3 good schools in the UK offer the IR ground, and anyone who thinks it's expensive can always make money by setting up their own TK school and getting all the approvals etc. No takers I suspect. As IO540 points out, when the JAA first started, nobody offered the IR exams!
But as much as I respect the Tk schools as an element in preparing youngsters to be 737 FOs with 250hrs, I absolutely agree there is no real requirement for the kind of cost base the JAA imposes for non ATPL candidates. The FAA is good enough to publish the entire theoretical knowlegde in it's various online handbooks - these are free and frankly the quality and illustrations are just as good as the commerical books. The method that works for the JAA PPL writtens could work just as well for the IR.
The irony with the gold-plate JAA ATPL TK method is that it is so long and laborious that cadets have forgotten much of the content by the time they put it into practice in modular training; especially the IR which may come many months after the final exams and CPL training. At an FTO I went to (having just done the IR exams) I couldn't believe the F170A process included completing a long open-book written test. I asked "how can this possibly be needed given everyone's done the JAA exams?" the answer was "oh, people have forgotten everything by now and they can get badly caught out by the examiners"
There is an article here on the JAA IR TK and a comparison with the FAA exam.
PPL/IR Europe - JAA IR Written Exams: Much easier than you think
Having said all that, I still think the difference between the 2 systems is not hugely meaningful in practice. The JAA system's bark is worse than its bite; from the outside it all looks terribly daunting. When you actually work through it, it's rather nice. The ground and flight schools are good, the question bank means that practically no-one fails a written exam, the 55hrs can be 40hrs of FNPT2 time which is not weather dependent and much cheaper than an aircraft and you can comfortably do 5hrs a day, the CAA examiners do their best to make the test relaxing and accessible.
The FAA
training system is superbly flexible and efficient; its focus is developing comptency and demonstrating that to a DPE; how you do so is unshackled by paperwork and approvals and all the other JAA stuff that I think adds little to the end result of training. However, other factors can make it less convenient. The whole Visa/TSA/SEVIS/Part141 school thing is a nuisance for training in the USA. You book two weeks and inevitably will be nervous that something at the end will delay your check ride beyond your return flight. Training in the UK and getting the checkride done needs a fair bit of logistics and planning to line everything up (still need TSA approval, Dft waivers etc) and I think is difficult unless you own your own N-reg.
The key lesson I've learned is to avoid agonising over the optimal solution, and just to do something; all of these methods look difficult until you start working on them, chipping away at the requirements and then it comes together.
On the FAA vs JAA, it's down to what qualification will suit you most. If you already have an N-reg or the right aircraft to buy/share is on the N, then the FAA method is the obvious one. But I don't believe the FAA route is sufficiently quicker or cheaper (any longer) to make it worthwhile moving an airplane from G to N solely for that reason. If you have an IMCr and good IFR experience and currency, then getting to the JAA IR (if that is your end goal) may be quicker via an FAA IR and conversion. If you were ab-initio going for a JAA IR, I don't think the converison route would save any time or money.
EASA may well improve the situation but 2012 is a long way away. I waited for the JAA "Instrument Weather Rating" that was mooted sometime in the late 90s. I'd still be waiting today! If you actually need or want to fly IFR now, waiting for EASA-FCL is crazy.
removing all content which is jet transport specific
The JAA IR exams have been already been successfully purged of Jet/ATPL content. The problem that remains is depth of detail in places, rather than scope/breadth.