Runtime includes?

[Justin Weinberg]

I have a service that's I can now standardize around about 100 different
"sections" of form content. Doing this will save me a lot of overhead of
having separate webs on a per customer basis.

I would like my customers to be able to use a tool and select from a series
of prebuilt (known at design time) form sections to include on their web
form page. All sections and their behaviors are known at design time.

Where I'm having trouble is figuring out how to get multiple webforms to
"concatenate" so to speak onto a single outgoing page. Ideally what I would
want is some sort of dynamic include ability as one would have with a script
language.

- I know one solution is to use web user controls and dynamically render
them onto a page as needed. My concern is that this could get unwieldy with
a lot of register tag prefix, and I have no data on performance with large
sets of user controls.

- I could stack all the controls on a page and conditionally make them
visible, but this is rather monolithic for my tastes and again, I don't have
performance data.

- Another solution may involve iframes, but I want to avoid frames if
possible.

- I suppose could give up on the single page and just have each section
presented in turn as its own page, but it would be clearer to the end user
if the sections were presented as cohesive units.

Any thoughts or suggestions appreciated!