It's such a crazy display on just how advanced the Federation really is that a small group of rogue Star Fleet officers were able to successfully leapfrog the cloaking tech to such a degree. There was another episode where the Romulans tried and failed to create that same technology but I can't remember if it was before or after Pegasus.

In DS9, a Vorta makes a comment about Star Fleet engineers being able to turn rocks into replicators and he really wasn't that far off.