I'm truly glad it worked out for you, and also that you can take all that trouble as lightly. That said, I beg to differ on one of your accounts:
If it really wasn't meant to be opened, Apple should be marketing their hardware (or certain serial number spans) as non-upgradeable, as opposed to providing a how-to sheet detailing how to open the casing to change the memory. As a software developer on Apples products, and knowing many others, I can note that hair-pulling is more of a rule than an exception with Apple, so I am out of excuses for them.
This exact "Apple experience" has been systematic to all my work on Apple products, so in the end, I find the degree of customer contempt coming from this company, in disguise of incoherent, incomplete, obscurely implied, and plain incorrect information, unacceptable. If they had improved the ratio of people actually working on products (and documentation is a technical fact-based product!), to that of people lollygagging in their legal, sales, and marketing, I am sure the quality and coherence of all their products would improve enough to make me more positive to Apple as well.
As it stands, I only wish that I, my customers, and my employer, and our mothers, could send Apple a bill on every hour wasted due to incorrect marketing (as opposed to documenting!) of their products, features, and API:s. All we want to know is the price tags, up-front. No excuses. Just correct price tags.