Web developer Vs ASP.Net developer

From Build Your Own ASP.NET 2.0 Web Site Using C# & VB, 2nd Edition

"Web server controls can be seen as more advanced versions of HTML server controls. Web server controls are those that generate content for you—you’re no longer in control of the HTML being used. While having good knowledge of HTML is useful, it’s not a necessity for those working with web server controls."

Hooray, so you don't have to understand what's going on in the actual HTML and HTTP.
I'm certain this leads to more people who know ASP.NET, but can't fix general problems.
"This doesn't display on this browser." or "Such and such data doesn't display right in these conditions." or "Not all the page gets displayed when I click on[X] on a specific version of a browser." How would someone who only knows ASP.NET and not how HTTP and HTML work have a clue at trying to solve these problems. Aah, yes they simply say that that browser is not supported, or it's a problem of the browser, network, PC, anything other than their code. The developer's problem goes away.
Customer/user/person has poor customer service.
Customer/user/person gets upset.
Customer goes away.
Huzzah, problem never gets reported again.
But that's not the end of it because the business loses a customer
Customer starts a negative feedback loop
...