Tabbing between fields of an NSTabView

Question

I recently reorganized a window that contained a large number of NSTextFields to instead use a single NSTabView, along with a couple of push buttons (OK, Cancel, etc). Previously, I had managed the tabbing order between fields by setting the nextKeyView of each field to point to the appropriate next tab. I'd also added the following to the View Controller containing all the fields:

- (void)windowDidLoad {
    [super windowDidLoad];

    MyViewController  *vc = (MyViewController *) self.contentViewController;
    self.window.initialFirstResponder = vc.YearTextField;
}

This worked really great and I was able to cycle through all the text fields in the order that I had defined in Interface Builder.

With the fields still in MyViewController, but now spread between a half dozen tabs of the NSTabView, the tab order is back to Cocoa's weird left-to-right tabbing algorithm.

I did reset nextKeyView for each of the text field, starting with the first field on each tab, linking to each subsequent field, then setting nextKeyView for the last field back to the first field on that tab. I suspect, however, that something has to change with the initialFirstResponder which (as above) has been setup when the View Controller loads.

Where/How should I manage the initialFirstResponder so that the field tabbing order is correct for each of the tabs in my NSTabView?

Thanks!