there are systems that work but its up to the trader to identify the weakness of the system. No system will guarantee 100% success rate. Take a look at Market Profile for profitable edge
Yes, conventionally. It was why I asked indirectly: "laggy" zig zag for knowing the sentiment of fast fractal? And I got a reply.ZIgZag is drawn post and amends after the fact, you’d know that if you spent two seconds looking at it.It can’t be used to predict.
Not sure what you mean by "a leg of a bar",but:
Take an up bar for example. Leg 1 is from open flag to the bottom, leg 2 from bottom to top and leg 3 from the top to close flag.
"To create a zig-zag chart, just connect extreme bar values;I use volume signals to substitute for the zig-zag.I also use re entry..."
From what i gather from the Jack`s chart,he uses sort of a Acceleration Volume,Deceleration Volume formula,which is clear seen from the drawn vertical Cyan lines(3 of them,at least).And he`s probably ignoring what`s in the middle,hence - "I also use re entry..." expression.
I am not up to date on Jack's approach. Ask him or read his old posts in his own thread if you are keen.
Listen up and listen carefully.. I'm here to tell you that the market is very complicated and it's very hard to understand. And if someone tells you different then they are full of it.. It's funny because I can explain the whole market to you in one sentence, but I'll bet you that you still wouldn't understand it.. Think about it for a second.. Do you really think you can be a good surfer by reading one sentence?
And in the upshot will find out that its rigged by high rollers and what we are doing is just catching a wave 
What is leg 2?
ZIgZag is drawn post and amends after the fact, you’d know that if you spent two seconds looking at it.It can’t be used to predict.