Wooh, it's very hard for me to understand well what you say. I'm not an English native speaker, so, please, try to use only very basic words, so I can follow your ideas.
"I see a neat professional subject line, "some changes". This indicates that you have work group experience".
Just one thirty years ago (yes, 30).
"Working hypothesis : "displayIfNeededIgnoringOpacity" method might need some interesting knowledge navigation to track down the description of."
I''ve already told you of an application which you can browse the doc with. It's MarshmallowLibrarian. But since sherlock has been greatly improved with the last OS update and MarshmallowLibrarian tends to crash repeatedly on my computer, I use Sherlock (just drop the developer folder on to the main Sherlock page), index it, and give it an enclosed string to search into documents.
Another good way to learn efficiently is to browse all the examples (see composite lab and sketch for images). Whenever you find a method you don't know, use find in PB with options frameworks only. You'll get all references to the searched method. Then browse the corresponding doc. There are also shortcuts to do it.
Another excellent way to learn is to subscribe to Cocoa Apple mailing list. Read, read, read it first, then ask people. And download examples when people give you a link to.
displayIfNeededIgnoringOpacity is well described in NSView:
Acts as displayIfNeeded, except that this method doesn't back up to the first opaque ancestor-it simply causes the receiver and its descendants to execute their drawing code.
The April Developer Tools CD is online now for all ADC members. If you have, as I do, a slow connection, you'd better buy it (20$). It's an about 243 Mb download. I've bought it on April 24th and received it today (I'm in France).
The main advantage is that you have the whole documentation updated (no need to go to Apple site every two lines of code).