[Elecraft] 44 ft. doublet magic lead length and "bats in my belfry"

[Doug Netherton]

I'm preparing to put a 44 foot doublet into my attic and I'm wondering 
if there is a magic lead length that allows me to work 10 to 40 meters 
with minimal Z on all/ most of the bands.  I plan on using either 300 
ohm twin lead or 450 ohm lead to a tuner with a built in balan.  Shack 
is close to the middle of the house immediately below attic, so lead 
could be less than 20 feet.  How about 22 feet times velocity factor of 
lead???  Any comments?

BTW:  I disturbed a furry flying insect eater in my foray into the 
attic, so I'm looking for potential entry points.  Any pointers for 
encouraging its/their departure with something like moth balls?

73, Doug, VE3MCF
k2 #1322