.Net portals too flimsy?

I'm pretty shocked at the exception handling that all of these .Net portals have (or don't have). I guess what I'm more shocked at is how a little piece of formating code could shut down a whole site. Take this for instance: I didn't like the styles that Rainbow was giving me to present my RSS feeds, so I decided to hack my own out of their pre-built ones. I got it working the way I wanted, but thought the spacing of the

tag was just too much to have in the RSS feed display, so I changed it to
. Now, I admit I have no experience and no idea how to write XML (yet), but my site threw a fit and wouldn't load the page because I didn't write the
as
. So sorry Rainbow! One mistake on one XSL stylesheet pertaining to one module on a page should not bring down the whole site.
DotNetNuke and CSK also had their share of problems with simple mistakes that were almost impossible to find with the stack trace information it displayed. Maybe it's different for web programming, but I would never let a program crash this way because of bad input by the user. It sounds like there needs to be more Try..Catch blocks.