I think Devon Diver has hit my point (it's buried somewhere in my posts!). If your cert says you've come from a IDC/CDC that has a reputation of pumping out DMs and instructors, as a shop, you have to be a bit wary, as minimal teaching does occur....
To be honest, I don't think the IDC/CDC center itself is the big issue. The IDC is just a
teaching course, not a
diving course. Given the parameters of the PADI education system, it doesn't take Einstein to deliver the material.
Also, the IE ensures a relatively level playing-field of
instructional ability, regardless of region.
What matters is
diving ability and breadth of
experience. That's something you
don't get from an IDC - it's something you gain from varied and extensive diving.
Most scuba industry employers place a (justifiable) emphasis on experience and in-water ability. In that respect, the 'zero-to-hero' types fall woefully short.
Thailand attracts a lot of backpacker-type travellers. They are often sold (or believe) that doing a zero-to-hero IDC in Thailand means they can work their way onwards during their year-break travels, typically with a goal of using their qualification in Cairns. Sadly, their typically deluded (or conned) in that respect - as their experience and diving ability will preclude them from serious consideration for employment.
I think it must be hard for them to accept that they wasted money on an IDC for their desired goals (which were unrealistic)...or are not the 'God-like' dive pro they (so quickly) believe themselves to be.... so better to blame this notion that it is 'all Thailand' that is biased against in Australia.