AdamFrisch
There are a great many people like you who go on concentrated courses of several hours per day every day for a week or two.
I'll comment more on the cramming for the written exam rather than the practical flying of such a course which I'll leave for another post.
I've seen the results of those courses and generally, as time goes on, they forget probably half the written and oral questions.
Take any experienced IFR pilot and ask them, years later, to re-write the Instrument Written exam in Aus, USA or Canada and most would score a lot lower without study to relearn what they have forgotten.
Most pilots never ever want to have to re-write that exam.
The IFR written exams, tend to be academic examinations in English comprehension, riddled with diversionary questions with double negatives that make even someone who knows the subject well practically likely to give a wrong answer.
While many of those double negative questions could be rephrased, it does make people think and a study a little harder which tends to add to retention.
The single biggest problem with IFR training is not the "initial training" but the absence of "recurrent and or on-going training".
Throwing IPC's every year or so in an exam style does not foster "on going training".
I believe IFR pilots and aviation safety would be better served by having a requirement to provide evidence of having spent a number of hours per month or quarter on "ongoing training".
I would suggest that you sign up and register for the FAA's large number of options for on-line ongoing training.
While there is nothing improper about 10 day cram courses, anyone going that route will need to spend significant hours studying AFTER their ride to maintain that level of knowledge.