Do you know the difference between single and double bracket notation? Why does Notes handle the URL parameters differently between the two notations?
When you use the single bracket notation, the specified URL is sent to the client, which then sends it back to the server as an HTTP request, creating a round-trip back to the server. The double bracket notation tells the server to perform an internal redirection, saving the round-trip to the browser and back, which should improve performance. However, because this redirection happens at the server, query string parameters are lost. This "feature" is not well documented and seems to have been discontinued in later versions of 5.0x. However, using the single bracket notation seems to work fine and is what I'd recommend.
This was first published in December 2001