As for seeing the back cast, there are different things I do. The primary one is to use a completely open (sideways) stance, which is how I can tell when the loop is weak (lack of sufficient tension). Another is video, but I'm having trouble finding a good place to do it where I can see the loop, so I'm just watching my mechanics. I've caught things that way. We have a lot of trees around here, but they are not usually dense enough to see the line. Where they are, I'd have to cast in the middle of a busy street or in a spot where there's a bunch of undergrowth where the line catches on weeds or sticks and leads to a crappy pick up. I wasted two hours the other day looking for a good place on a golf course. The snow covered the debris, but created too much glare for my old iPhone, even with the sun behind me. When I finally found a dense enough stand, the sun had melted off the tall grass, weeds and debris. Grrrrrr. In disgust, I went home. I'll keep trying to find a blue wall somewhere.
In my search, though, I may have found a faded green one in the parking lot of an indoor tennis club. I'll try on the weekend when there aren't so many cars there.
I'm also working on pickups anywhere from 40' to 55'. There certainly is more feel with more line out of the rod tip.
As mentioned to Lasse in a side conversation, this is for my own casting so that every pick up back cast has adequate tension. It's also because every casting task on the CI exam starts with a pick up and the loops are judged.
I've not read Bahadur's article, so definitely will do so today. Thanks for pointing me to it!
