As you noted, the financial advantage does not apply to Facebook. Contrarily, there's a financial advantage to shipping a better product, if you can afford to do so.
I'm interested in your supporting argument for other governing factors or software as a social activity, and how that relates to making engineering choices that sacrifice product quality for some notion of engineering perfectionism.
No, he isn't. Another way that a UIWebView can provide a super experience to custom NSViews is if the UIWebViews implement more of Facebook's functionality than the custom views, or if the features the UIWebView expose match the ones users want better.
