I recently had a dipped headlight bulb fail on my Citroen C5. Unfortunately within 24 hours, and before I could replace it, the second dipped headlight failed. As it was at night and my car has no foglights, I had no choice but to call out the AA.
The AA man said that with modern wiring systems, it is quite common for a second headlight bulb to fail shortly after the first due to an electrical surge.
As the headlight units are hard up against the battery on one side and the hydraulic reservoir and the pump for the power steering on the other side, the AA man ended up taking most of the front of the car apart just to replace two headlamp bulbs. This took about 2 hours on a freezing cold and very dark night! He said that many modern cars, including VW and Fords are equally bad in this respect.
Bearing in mind that my car is of French origin, where it is a legal requirement to carry a spare bulb set, the difficulty of changing headlamp bulbs is a dangerous nonsense. Even if I had the bulbs, I would have no chance of fitting them myself. It might just be possible if you have very thin double jointed wrists and fingers like ET!
In older cars, changing a bulb was about a two minute job. As cars with blown headlamps are a safety issue, surely cars should be designed so that it is easy to fit replacement bulbs!