Geometry.

Most bicycles have a 70 degree seat tube angle. But when I was a kid,I had a bike with a banana seat which you could slide back on. Thus, I got used to leg extension, while maintaining a low center of gravity.

When I was 12 years old, I sought a bike with a banana seat, but larger than the 20" wheel bike I had.

I joined the International Human Powered Vehicle Association http://www.ihpva.org
back in 1985 or '86. at that time, there were only 2000 recumbent bikes in America.

Being an Engineering student, I wanted to build a machine to patent and make a profit selling.

I did not want to build a true recumbent, which has a seat tube angle of zero degrees.

All I wanted was a bike with 26 inch wheels and a banana seat. But I also asked for the "impossible".
I had to have a fiberglass cargo box on the front of the bike, not attached to the handlebars, but attached to the frame, to carry 100 pound loads. And said box must be aerodynamic.

So, in 1991, my 6th cousin Mellisa asked me to adopt her. Good, I was in the Navy and needed someone to run my bike business while I was overseas. She invented the Fiberglass Ladies Bicycle.
Here is a picture:

As you can see, the seat slides back so the rider has a choice of position, like a banana seat.
The cargo box is based on the roof spoiler of a diesel truck. Good crash protection! I should point out that fairings (motorcycle windshields) are mainly for protection of the rider, and aerodynamics is a second consideration.
There is a synergistic effect between the heavy box and the seat position. If you had a box like that , and you couldn't move back, there would be a tendency to flip you over the handlebars.

$270.00 went into this bike, and so many kids were begging for me to sell it, I had to say $3,000.00 Or Best Offer. I actually recieved $1,215.00 for this bike. ( A guy bought it for his girlfriend). If I had commercial/industrial real estate, I'd put this bike into production.

The secret is out: People Want a Bicycle seat that is further back, and they can ride confidently without feeling like they are going to fly over the handlebars.

The bike pictured is type 9, there were some other attempts previous to this one. This bike is a "blivet" which means it is ten pounds of s _ _ _ stuffed into a five pound bag. One example is the aerodynamic fairing and cargo box, being the same piece of fiberglass. It's too much at one time. I should've built a plain box, without aerodynamics, OR , I should have built a windshield (fairing) without any cargo space inside.
A bike company only needs ONE improvement over existing bicycles. That can be their main selling point.
In this case Electra http://www.electrabikes.com
has a bike that will not send the rider flying over the handlebars. One idiot threatened to sic the Federal Trade Commission on Electra, claiming Electra is a monopoly. But Electra is only a small bicycle company, no where like a monopoly. ( that was a stupid thread from a month + ago.)

The main advantage of the Townie Geometry is that the rider feels safer; the bike will not flip the rider over the handlebars, and the rider can put the HEELS of both feet on the ground when making a stop.