>>there are cram shops in India which 'train' you to clear Google/ Microsoft interviews.
This is so true, that I can't even find ways how to assert it more.
As a fresher, I attended a off campus interview here in Bangalore(Those who don't know- these are generally mass hiring drives, where hundreds/thousands get hired) where I happened to talk to a guy between written test sessions who even had taken very elaborate 'class notes' on clearing these interviews. He had gone through something like a 3 months coaching class just to attend these interviews. There are standard coaching materials, which are updated pretty frequently. Pretty much anything that they can ask you in these interviews will be covered. They have made you hard practice it so much it will be cake walk to you make it through.
>>And this has been going for at least 6 years
I can assure this has been going on for a very long time now.
>>It's all very funny and ironic.
Its all about the volumes. A recruiter told me, if a resumes falls down during a mass hiring drive they don't even bother to pick it up. We live in an era where recruiters search monster.com based on some keywords and pick up candidates based on that. So we are now down to SEO optimization for resumes. And then coaching classes to game the interviews.
As a side note, in all major IT services companies in India you have to take 'certification exams' for pay hikes and promotions. I've seen people drop everything they do and practice clearing these for months. The worst part is you have to 'memorize' the whole material. Later I would see those people go on to get promotions and hikes, while the actual who go the work done fail(due to lack of time to practice) in the certification exams.