A couple of thoughts:
"Still another objective of the instant invention is to provide an indicator for law enforcement that hub integrity is intact before allowing trailer placement within a body of water...... "
- Is this a US thing? It's not the usual thing to get nicked for over here -"excuse me sir, you appear to be using a failed oil seal, please escort me down to the station....." (or in a more Sweeny styl-ee "oi, you're ncked"
"The air compressor 50 is preferably mounted on the trailer in close proximity to the hub assembly wherein electrical power may be obtained through the
trailer harness for connection to a car battery "
-On a boat trailer???????
"The use of a conventional air pressure gauge ....."
-That's not going to last 5 mins on a trailer -it'll get vibrated to pieces.
"Since the leak has not been actually been repaired, the pressurized grease continues to be ejected into the water when the prior art devices are used."
-Especially as you've put extra pressure into the system with your compressor! There is also the small point that isn't the problem is that water is ingested, not that grease gets out........
The patent also doesn't take into account that by adding a compressor etc you have just reduced the carrying capacity of the trailer, and that if you get a grease leak, it's kind of obvious by the black sticky trails that run outwards form the hub......
I think I'll just carry on using the grease gun!