Michael
If you want a thorough exposition of the benefits of AOLServer + TCL + DB as well as how OpenACS can help you check out:
Philip and Alex's Guide to Web Publishing. (The link seems to still be there despite the Arsdigit situation)
If you're working on an application that involves getting info in and out of a database via a web interface this platform will allow you to do it easily.
The book goes into all the issues including: Scripting code (Tcl) vs. compiled code(Java), the database api and the database pooling aolserver does, the importance of page flow and data mode, etc. etc.
Open ACS gives you a wealth of useful functionality right out of the box. But say you weren't going to touch one bit of OpenACS functionality and do your own application from scratch (the application I am working on has very little to do with collaborative web publishing) the wealth or information that the OpenACS community has is huge. What I mean is if the answer to your developement question doesn't already exist in the message boards or in a help/documentation file chances are that someone in the community has already had the problem you have and will know the solution. There are alot of really smart people reading these message boards. This works to everyone's advantage as the one asking question will eventually be answering.
As an example of the wealth of knowledge to be found here's the link page I use to find answers to my questions:
Rob's Web Publishing Links. (Some of the links may be old. Sorry. I don't have time to fix them right now.)
In any case the application I'm working on probably never whould have been accomplished using any other platform. In addition the thought of coding the thing in Java is painful.
