Lardy collar conditions dogs in the continuous mode. But like Howard said, it is a very short burn, like "one thousand and one" for the duration. He might do a 1 1/2 in extreme cases. He warns against holding it down continuously until compliance is achieved, like for3-8 seconds. After that Lardy switches to the momentary mode for force to the pile, etc.
What Evan said is mostly true about the conditioning of dogs to here in other programs. However, Lardy advocates and early here conditioning if the dog is a wild child and doesn't want to return promptly. Of the last few dogs I have trained I did an early here conditioning for: Rowdy, Major and Briley. But didn't for: Hank, Scout and Cabbie Lou. I would guess that I am about 50/50 on this process.
Hope this helps.