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"Semi-Auto" Gearboxes

Before people condemn the new-breed of "semi-automatic" gearboxes, 
one should have the opportunity to drive a car with these installed. 
Semi-automatic gearboxes or sequential (their proper name) name have 
been around for quite a while now. 

Almost ]every top WRC rally car has them as standard. Their acceptance has
lowered the price,
that they are now filtering down to the privateer. I remember reading
several years ago that the
price of one was about $45K, I believe you can get one a lot less

They allow the driver to change gear (up or down), while having the throttle
to the floor, the gearbox electronics performs the clutch release, the  gear
and the electronic version of a toe-and-heel. There was an article in "Cars
and Car Conversions", 
which had the editor drive 2 cars, one with and the other without the
sequential gearbox. 
They ran on prepared stage and compared times. The editor estimate that the
gearbox was saving him approx. 1/3 sec. pre gear change. Now translate that
to the 
number of times a rally driver changes gear on a stage and the accumulated
soon adds up.

The ones I have seen installed, usually have a 
gearstick, but instead of the usual "H" pattern, they only move forwards or
backwards. A push
on the gearstick instructs the gearbox to shift up and pull on the gearstick
downshifts. You
still need to use the clutch to start from a standstill. Reverse is engaged
by putting the gearbox
in neutral, depressing the clutch and depressing a button on the dash.