Aviation professionals are familiar with the title. Dual systems mean you have a backup when one fails. Dissimilar means they are different, so the same kind of failure cannot affect both systems on the same flight.
A breakdown when driving between cities in the early years could result in danger, or a delay of up to several days.
The Model K has dual dissimilar ignition:
Buzz coils powered by dry cells, and
Self powered high tension magneto.
The two systems are complementary in the fact that the buzz coils put out full spark for hand cranking, and the magneto saves draining the dry cells during extended running. Either one would get you home after a failure of the other, as they have complete redundancy from the switch to the sparkplugs.
The Model T has partially redundant ignition - the power source: if you buy a battery.
Actually, the Model K had two dissimilar systems, and a third method available if the mag failed. From the 1907 op manual:
When I first bought into this hobby, I was of the impression that the Model T was little more than a power-mower wearing a car suit. Wrongo! The Tin Lizzy taught me that inexpensive didn't necessarily mean cheap and simplicity could be elegant, as opposed to primitive (and yeah, if my magneto packs it in, I can limp home on the storage battery).
At the same time, I was surprised to discover that other brass-era cars like Locomobiles, Packards and such were possessed of a genuine mechanical sophistication even in spite of a lack of semi-conductors and computer-chips. Turns out the slide-rule was invented in 1620. Go figure, huh?
"For starting motor ..." I interpreted at first a starting motor, which didn't make sense. It should be read, "For starting (the) motor..."
Rob, have you rearranged the plug wiring to match the above?
Bob, agreed. All the important mechanicals, including 4-wheel brakes, had been invented before 1915. Electronics is the only thing in life where you get more for your money every year.