but could it be the that bloke who dumped the rope was not the one who knicked your pot but picked it up in the ocean so as not to be a hazzard to other boats and was it complete or cut off by prop or knife and maybe not stolen but lost!

Ah forgot about hypotheticals. it was cut at both ends so I assumed it must have been stolen and dumped. I do apologize for anybody feeling wrongly accused. I didn't realise pot rope free floated around, have never seen it before myself.

 or maybe they cut the float off and kept it.............it's just that every time someone loses a pot it automatically has to have been nicked 

Yeah spook if you  were the type to steal a pot,  dont you think the first thing you would do would be to discard all the identifying details. Its much more likely that someone found the rope and returned it to the only place they could, But I understand your pain. if it wasnt for the fact that fisheries have the right to pull your pots to check they are legal, you could come up with some fun ways to detere the a**holes  but these days its not the done thing , and there are some good reasons for it too.

About 8 months ago coming back from the ffb, we were heading back to woodies, when last minute we spotted a crap load of pot rope floating in the water. we came to a stop real quick before getting the rope wrapped around the prop. obviously someone had either picked up the rope earlier in the morning and decided to cut the float off and leave the rest there, we managed to pull the whole lot up. 50 metres of rope and jarrah cray pot, this being in 8 mtrs of water. Now this had obviously been in the water for a very long time, it was barnacle encrusted beyond belief. We took this back to the ramp, and unloaded it next to the bins. Now sometimes people try and do the right thing and make it safe for other boaties and fishers out there. Would hate to think what would have happened if it was at night and we didn't see the rope.

Yer, we have found a few ropes in the past and just take them back to the ramp, drop them of at the fisheries shed.

Some thing I dont see much now days, is when people get snagged on a cray rope and lose a rig you should tie a rag or something between the floats to let the deckie know that something is wrong with the pot/rope.

not a good thing having a sinker and a set of hooks comming over the side and around the winch.

I actually carry an old red shirt to cut up in case I ever inadvertantly snag a cray line - saw a deckie in Jurien almost brained by a 24 ounce sinker and two 8/0's (not mine) and have carried the shirt ever since - hope others do the same 

Have come across several loose floating cray ropes clearly cut off by props (or theives perhaps) however I always recall many years ago a professional dive boat operator who had absolutely no compunction in driving over cray lines indeed his stainless prop blades were super sharp on the edges

I'm not suggesting for a second it was the case in this instance, but I have seen some craypots put in some stupid places, that are just asking for trouble. On the weekend, there was two pots placed on a small piece of reef that runs north from Carnac between the Freo heads and Thomsons Bay; probably the busiest piece of water in the state and over the Easter weekend. Personally, I wouldn't fish there, never mind place craypots there.

Are there rules that govern where pots can be placed or is it left to people's common sense?

Ha yeah, definitely one of those idiots that puts pots on the leading Lines etc, I fish at night so I can't stand those idiots, you have to drive up mark it while its light so you don't do yourself mischief later on. I do add and take away rope to suit depths aswell so no one would hit it with a prop unless they drove over it. I'm Going to dive it to see if its there anyway, once they know how that poor bloke went missing.
Fishy fingers, had heaps of pots flogged, never care as it goes with the game, it was just seeing my rope cut and dumped this time. I have lost them to swell etc aswell, sometimes they move around too. When you have good weather and all your rope is cut from the floats to the pot you sort of just know someone has pulled it all the way up to cut it and probably didn't drop it back down, it was bloody heavy too.