I travel with my dive gear every other month. I have a knife attached to my BC in my checked bags. I've never had a problem.
Because of the dive gear they always inspect my checked bags, but I have never had them refuse the bag or remove any gear.
I am currently on a trip in South Florida. The bag was x-rayed and inspected in California. The TSA folks did something interesting. They left a note inside my checked bag, telling me that they inspected the bag. They also zip tied the main zipper. Since I can't carry any sharp objects on the plane, I had no easy way of cutting the zip tie. I ended up using my rental car key as a saw. I took a while, but I cut through it.
Have a wonderful trip
Regards