My experience with TclPro and the ACS (about a weekend's worth of experience) is similar to Carl's.
I couldn't get it to keep my breakpoints between invocations, and so in the end, I have reverted to ns_log style debugging.
Currently, my development environment consists of Emacs with an nscp window for tcl testing, a pl/sql window for sql testing, and David Lutterkort's extensions to emacs to prettify/color code server logs and help one copy queries from the log into your SQL buffer (binding variables along the way and with realtime tailing of the server log.)
Throw in a dose of ACS 4 developer support (to easily track headers, cookies, and timing of queries) when I can, and my nsvhr patches to AOLserver (which can be used to get HEX/ASCII dumps of everything in or out of your system), and what do you got?
A very sophisticated world of printf debugging.
Sigh,
