Modern humans always need to wait. We wait for bus, and then on the bus, we wait until it brings us to the destination, etc. If you do nothing during these wait, your life is effectively shortened. So what can we do?
Firstly, some people might suggest you to find something meaningful to do during the wait. For example, to bring a book and to read it whenever possible. This seems to be a reasonable suggestion, provided that you always have something meaningful to read or to do during the wait. With mobile technology, you can use your mobile phone, or even on the Internet at any place and at any time. Not bad, right?
Secondly, some people might suggest you to minimize the amount of waiting time. For example, instead of taking public transportation, you drive your own car. That could cut the waiting time effectively. However, you cannot do anything other than driving, except maybe listening to music and radio.
So which way is more time saving?
By taking public transportation, given that you have something meaningful to do, or to read, you are wasting zero time during the wait. This is what exactly pipe-lining do inside a computer CPU, the functional units are always busy. So with this metrics, public transportation is better than driving.
However, we are isolating the single event of transportation under this setting. Suppose you are going to catch a train or a flight after the drive/bus, if you missed the schedule, you are going to waste even more time! So, in this situation, wasting a little bit time for driving, you save a lot of time waiting for the next train/flight.
Therefore, there is no single rule which yields the best result. The idea behind is to maximize the meaning of your waiting time, and at the same time, try to minimize your waiting time. Like the above case, instead of driving yourself, maybe you can take taxi which you save virtually the same amount of traveling time but yet, you still have the option to read/do anything meaningful during the traveling.