Question about the pure theory of a dipole

[K8BBL]

1) I'm asking about pure theory for my knowledge. I know that in real life an 80m OCFD that is off a bit will be compensated for by the tuner. My old Icom 746 does this very well.
2) Look at my sketch. Assume it is insulated wire for the 'legs' of the dipole.
Question 1: In pure theory, if I need a 100' 'leg' where would I measure from (A-D, A-E, C-D etc)?
Question 2: If the length of the total wire is 100' and the length from D to E is 3' (and is folded back over itself) would this , in effect, make the total length 97' or does it not matter that it's folded back and I would still have a 100' 'leg'? This is insulated wire, no connection from E to the 'leg'.
Question 3: If the insulation was stripped off the 'leg' and E was electrically connected to the 'leg' (3' back) what would the effective length of the 'leg' be?
Thanks in advance for the lesson, I appreciate it.

 

[prcguy]

If you fold the wire back on itself the current on the folded back section will be flowing in the opposite direction and will cancel radiation making the total length of wire less. If you start with 100ft and fold back 3ft tight against the main wire you will have an antenna that is about 97ft long.

 

[K8BBL]

For my further clarification: if I fold back 3' tightly against 3' of the leg I am using 6' of my leg to make 3' of doubled wire. Do I lose 3' or 6'? In other words, does my 'leg' end where the doubled portion starts or where it's tied to the insulator?

 

[WA0CBW]

What you "fold back" is no longer part of the antenna. If you fold back 3 feet then the leg is 3 feet shorter. However, the amount folded back can affect the the actual length depending on how much is folded back and how tightly it is wrapped.
BB

 

[prcguy]

Whatever the linear length is after folding is your antenna length. Take 10ft of wire, fold back 3ft on each end leaving the wire 4ft long, you now have a 4ft long antenna.

For my further clarification: if I fold back 3' tightly against 3' of the leg I am using 6' of my leg to make 3' of doubled wire. Do I lose 3' or 6'? In other words, does my 'leg' end where the doubled portion starts or where it's tied to the insulator?