Hi
Ok let me explain you briefly
There is one only instance of TIWServerController, per application, and should only be use for writing only in the main-thread (OnCreate / OnConfig).
Then there are as many sessions as browsers connected, and for each session, a list of IWForms / IWUserSession or Any oher data modules, that are owned
Everytime a request is done, like a button click, you are working in a unique instance of a Session, IWUserSession, IWForm or DataModule.
If you have more sessions opened, there will be another relative instances, so it's perfectly save to write them concurrently.
Another thing, is data pooling, also existent in Intraweb, is DataModulePool, to share the same data between a given number of sessions.
P.S. Sorry for my poor english
You don't have to apologise, we understand you very well, we face the same problem, I hope Shakespeare forgives us all