Whats the point of heavy braided line with less strength leader line?

You know, everyone will have a different take on this, but my thoughts are this. If I have to use a leader to fish a braided line, I wont fish it to start with. And no matter how much "spin" is put on an answer in an attempt to make a leader on braided line sound viable, I refuse to accept it. I'm a bass fisherman using casting equipment, not a fly fisherman after a trout. You are absolutely right in your thinking.

I have no idea what your talking about I just thread my hook threw and I've got 65 lb test

Several reasons. Fluorocarbon is much more elastic than braid or superline. Also, fluorocarbon degrades in the sun over time, braid, or superlines for that matter, are not affected. Some fish don't care about the line, others are spooky. One lake I fish, I won't fish without a fluoro leader because it's very clear. Other lakes and rivers don't matter. However, as for the test, it's best to tie lines together that have the same diameter, for one. Since braid/superlines are thinner per pound diameter, you end up with a lighter line leader than the main line. Another reason that someone else mentioned, is breaking. If you're going to break off, would you rather lose 18" of fluorocarbon leader, or 65' of braid and ruin your day fishing? I'd rather just lose 6" of my main line by needing to tie on a new leader. Oh, and one other thing I forgot, is when you don't use a snap swivel, and you tie the line straight to the lures, if you switch lures often (as I do), you will burn through your main line fast. But if you tie on a long 3-6' section of leader, you can switch lures several times and not lose much length. And when the leader gets too short, just tie on a new one and you got the length back.

Ignoring fly fishing there are two answers to this. If you are fishing with a float (bobber) or a leger (sinker) then there is a very good reason for doing it. Sometimes when you hook a fish it is going to take you into snags and you are going to lose it. Sometimes it is just going to bust your line and get away. If it does, you don't want it trailing 100 metres of line and two ounces of lead from its mouth. That will end up killing it (and leaving you with insufficient line on your reel). So, if you have a leader that is going to break before your main line and a sinker that is set up so that it falls off the leader when it snaps you will be fishing much more humanely. Add to that the fact that using leaders that are fine and/or invisible is much better at fooling fish and the argument for a weaker leader becomes very strong. If you are fishing with lures though it is a whole different ball game. Lures can cost a fair bit of money and if you use a weak leader you are going to lose a whole lot more of them when they get snagged as you cast and retrieve them. The leaders will snap as you pull to get the lure back. Even the best lure angler will cast into a tree or reeds, or get caught on rocks at the bottom of a river/lake more than once in a day. Add to that the fact that fish caught on lures will struggle to take you into snags at all often (I can't even remember it ever happening to me). So, with lures there is no case for using a weak leader and I never do. As I fish a lot for pike I actually use wire traces that are very strong indeed.

Braided line is not cheap. That is why a lot of fisherman use a leader that is lighter than their braided line. I think if you use a leader that is the same pound test as your braided line...you would have a leader that is too heavy for certain fish. Besides that if you got hung up on something and had a leader that is the same pound test as your braided line, you will be in one heck of a struggle to try and get your hook/swivel free from whatever it is hung up on...then most likely have to cut a portion of your braided line.

With a heavy main line and a lighter leader, the "weakest point" will always be on your leader. You don't have to worry about the line getting nicked 20 feet up from the end, or the entire spool of line getting old and weak from sitting in the sun all day. All you have to do is replace your leader when it gets old or scraped, and you'll be good to go.

So it breaks at the leader. Fishing isn't perfect. You don't make the best cast, sometimes you run your lure, bait, rig into something that is immovable. Instead of donning the scuba gear and spending hours of time retrieving that .25 cent worm you snap it off at the leader. You can get more lures, and terminal tackle...you can't get more time.

Several reasons. Fluorocarbon is much more elastic than braid or superline. Also, fluorocarbon degrades in the sun over time, braid, or superlines for that matter, are not affected. Some fish don't care about the line, others are spooky. One lake I fish, I won't fish without a fluoro leader because it's very clear. Other lakes and rivers don't matter. However, as for the test, it's best to tie lines together that have the same diameter, for one. Since braid/superlines are thinner per pound diameter, you end up with a lighter line leader than the main line. Another reason that someone else mentioned, is breaking. If you're going to break off, would you rather lose 18" of fluorocarbon leader, or 65' of braid and ruin your day fishing? I'd rather just lose 6" of my main line by needing to tie on a new leader. Oh, and one other thing I forgot, is when you don't use a snap swivel, and you tie the line straight to the lures, if you switch lures often (as I do), you will burn through your main line fast. But if you tie on a long 3-6' section of leader, you can switch lures several times and not lose much length. And when the leader gets too short, just tie on a new one and you got the length back.

Braided line is not cheap. That is why a lot of fisherman use a leader that is lighter than their braided line. I think if you use a leader that is the same pound test as your braided line...you would have a leader that is too heavy for certain fish. Besides that if you got hung up on something and had a leader that is the same pound test as your braided line, you will be in one heck of a struggle to try and get your hook/swivel free from whatever it is hung up on...then most likely have to cut a portion of your braided line.