using the clipboard for communicatign between programs

[mnrvovrfc]

Microsoft discourages usage of the clipboard in this manner but if it works for your specific purpose then nice.

Did they give a reason to go along with discouragement?

Some people went as far as copying and pasting passwords, credit card data and stuff like that and were hijacked for it, didn't know a malicious program was able to force copy into the clipboard somehow, or block the attempt by the system to clear the clipboard. It must have peaked off enough people going into or out of a web browser then trying to paste text somewhere. Like when I tried one of @Pete's programs to trigger an URL that resided on the clipboard.

In the past a malicious program could put something into the clipboard to disable something in Internet Explorer. Other things could be done that way because a few companies insisted in providing data into or obtaining data from the clipboard, from paying customers. It sounds paranoid, because there's Data Execution Prevention and stuff like that to check certain sensitive areas of RAM periodically. However, it might be a reason why Windows Defender and/or anti-virus slow things down where they don't have to (eg. computer kept totally offline for weeks).