Has anybody in human history ever casted one of these 5 times consecutively without the the hooks tangling with the line?

Yes, but they do tangle fairly often. Good lure though, especially in low light conditions.

I've had the hooks tangle a couple of times, but its nothing like a Mann's 1- minus.  

It may be the way I cast, but I rarely have the problem of a Jitterbug hooks tangle in the line.  I use 20 or 30 LB. PP with a 24" Floro leader.   I do have a problem with the Jitterbug's rear hook fouling with the front hooks.

I never really have the hooks getting tangled. But the way I cast could affect if they tangle or not...

Hardly ever, and I fish them hard

If you "feather" the line while it feeds out, you can keep the lure (and especially the butt end) ahead of the line better.  You lose some distance but it will help.

My problem with the Jitterbug's rear hook fouling with the front hooks maybe due to fishing a lot of rock cliffs, a rock face 3 to 20+ feet off the water.  The lure often hit the rock cliff.

Aim for a spot about 10 ft in front of the cliff, do not even look at the cliff. I also switch out the stock hooks and put split rings on the hook hangers.  I use the 0 shaped ones, as there was discussion here about using the oval ones, and I use the 0 shaped ones.

If you "feather" the line while it feeds out, you can keep the lure (and especially the butt end) ahead of the line better. You lose some distance but it will help.

I thought that might help but it doesn't work for me.  I wonder if it's a spinning vs. bait casting thing?  Is it that the people who don't experience snags are using bait casting reels?

I switched out the stock split rings and trebles, don't really have this issue anymore.

What did you put on?

Try bit of a heavier leader of like 17# test fluorocarbon between your main line and the jitterbug. Don't have to be long. Two feet is plenty. It helps keeping the lure from tangling and keeps the gurgling going nicely. Great suggestion earlier about "feathering" out the line on the cast too!

I use a baitcaster and 12lb mono.  I have not had any problems with tangles.  I have had the front and rear hooks tangle though.  I will check into the 0 shaped hooks.

I used to fish the jitterbugs a lot and had this problem, but I think muddy is right on.  The split rings should help, the way the hooks hang from the factory doesn't allow them to move very freely.  I will definitely be trying this next time I'm throwing a bug!

you could just remove the treble hooks.

What size jitterbug are you using??? I had the same problem with the 3/8 ounce size, moved to 5/8 ounce...problem gone. It is big enough the hooks can't tangle themselves.