I'm not sure if I could throw the top into a Frisbee on the ground. But, controlling the top in my hand is a skill I'll only need IF the silly thing ever comes back.
50 throws to get 1 to the hand is just about what it took me. But that was AFTER I could consistently hit a Frisbee target or a particular tile on the kitchen floor. I also think that you need the skill to control the top in you hand before catching the boomerang. I was fortunate be able to watch a friend easily catch tops with extreme amounts of lean (more that 45 degrees).
Target shooting also will force you to develop consistent winding and throwing methods. To avoid the fluttering issue, be sure the knot is far enough down away from the crown (near the wide part of the top) and that you have plenty of tension from the crown wrap to the tip (a firm pull but not a gorilla pull)
* Start with the target at the natural distance from your feet. (Where your spinners land) Put the target to your left near the same line as your toes (opposite for lefties). After you can hit 5 of 10 or better with a relaxed throw, then move to the next steps.
* As an exercise, pretend the the Frisbee is on a stool about knee high. With the higher aim, work on dropping the top straight down into the disk. This will require a moderate pull back. Then put the Frisbee closer and closer until it is right in front of you. (Rachel says "Don't wear sandals.") Keep the same aim point and throw, but pull back more. Since you can by this time drop the top at your feet move on to the next step.
* A minor adjustment to pull up more will bring the top to your hand. (Rachel says, "Remember to keep the same style of throw as when throwing a spinner to the ground. I found that I was unknowingly 'adjusting' something in my throw when trying for a boomerang, and the top kept coming back sideways.")
* There is a Huge satisfaction in getting the top to your hand even if it bounces out or leans to far to keep.
* The last critical steps are to have "soft hands". Relax and let your hand fall a bit to follow the top. Bend your knees as you catch. Otherwise you will have a nice top in your hand that just bounces off. (ask me how I know) Take a step or two to chase it down or catch with left hand if needed.
* Be sure to mix it up. Target far, Target near, Boomerang attempt, skyrocket, scoop, use a power spinner for hand control practice.
I was asked, "What is your favorite trick?" After some thought I decided that it is the boomerang. It was very hard for me to learn. It makes you look like a great expert. It is the gateway to almost all other tricks.
Have fun, be persistent, let us know how you are progressing.