Hi, Ramani!
Your comments are spot on. I had simplified the problem statement to focus on the issue. What I actually do is to have the text box collect a new string to be appended to the existing string. The form has two text boxes, the top one being read-only, showing the existing text. The bottom one is for the user to enter text to be added. There is no way for the user to edit the existing text. This became a requirement when an account rep was caught "fixing" her incorrect special instructions after an order was sewn wrong.
(The application supports an operation that embroiders logos and such on shirts, jackets, hats, etc. for corporate customers. The text involved is for "Special Instructions", details that need to be communicated to the Production folks. Sometimes an order may be for 5,000 units. If they screw up some detail, they may have to redo the order. When that happens, they like to be able to figure out how things got screwed up.)
I show the name/date/time in the "new text" text box to remind the users as they enter these Special Instructions that they are responsible for getting it right.
One more detail: the new text is added to the beginning of the existing text so that the notes are displayed in newest-to-oldest order, newest at the top.
Thanks for your comments,
Shanachie