4 secs booking is not possible at all.
There is NO S/w made that can bypass/detect Captcha in less than a second.
Also Netbanking pages, there is NO Autocomplete.
I myself completed Manual booking with Auto Fill Passenger details in 42 secs.
19...
more... secs is a slight probability.
But anything around 20 secs and more are high chances of using of softwares.