What got me with the Casey Denault story was how easily Lucy was hoodwinked. You would think that over the years, Jock, JR, and Bobby would have warned her about con men.
I believe Lucy was warned about con men and she even got some education in that department through her experience Allan Beam and then with Eddie the construction worker she was sleeping with while he was also sleeping with Betty.
Lucy knew about con men, but Casey Denault was apparently designed to be a con man so good that Lucy couldn't see through it and would have gotten taken for a ride had it not been for April's help. Knowing about con men is one thing, but being able to detect them is another.
While Casey Denault was supposed to be a very skilled con man, I don't know if the actor convinced you that he was "that guy." Did you find the actor's performance convincing? Whether it was all the actor's fault or a combination of the fault of the script as well as the actor, I didn't find the character of Casey Denault as being convincing enough to where I could believe he was as good of a con man as he was supposed to be.