Agree, the biggest tall stories I've ever heard are croc stories.
I spent nearly 10 years as barra guide in the waters of FNQ and the top end,arhnem land.
Had some excited clients tell me they saw a 25 footer up this creek, they took me to show me, and it was a big croc, about 5m and a bit long, probably close to 17-18 feet, but not 25!
Even the "sweetheart story" is dubious. I reckon that the real sweetheart is alive and well, in captivity at green island in Cairns. Came from the same lagoon as the they claim to be sweetheart. But if you know the story, sweetheart had thing for outboard motors, and used to try and eat them....while they were running! Cassius(the one on green island) is missing parts of his lower jaw, and has lots of head scars. The one they call sweetheart, in the museam in Darwin, barely has a scratch on him.
I'll post some pics of crocs one day, I used to do shows in tourist parks in Qld during the off season as a fishing guide, my favorite one I worked with was jack the ripper at kuranda, he got his name because he killed every other croc we put in with him, mostly girls.