Tcl 8x was very slow with the ACS when it first appeared because each page in your installation was recompiled for EVERY PAGE HIT. Procs (i.e. your entire tcl directory) were compiled once and saved, but pages aren't wrapped in a proc and the server source's them directly.
Rob's modifications include caching of compiled bytecode for pages, as mentioned elsewhere. This removed the "compile for every hit" overhead, substantially speeding things up.
The sequence, as Roberto mentions, is that he wrote our docs, Rob made his improvements, and the docs sat unchanged. Thanks for noting the contradiction of the docs with other statements...we need more eagle-eyed critics!
