If an incandescent "lightbulb goes", it is quite likely that a portion of the "blown" filament will "land" across the connections protruding into the "bulb" and cause an almost short-circuit, thus tripping the breaker.
For your question of why "this particular light keeps blowing the light bulbs every 3 weeks", I cannot suggest a solution - except to replace it with a suitable LED.
However, please be aware of the problems in enclosing "replacements" for incandescent lamps into inappropriate enclosures. (See
http://sound.whsites.net/articles/incandescent.htm at about half-way down, where "CFLs in Existing Luminaires" is discussed. Much the same applies to LEDs in these inappropriate situation.)
He refers to cents so I would think from USA, since they have a different voltage he is not testing the same lamps as we get here, we it seems like dimmers, to work with a dimmer an LED lamp has to not use the switch mode power supply as these would correct the power removed by the dimmer so would not dim, and also there has to be a few milliamp drain to work the dimmer so the lamps are fitted with a bleed resistor, the EU has said it has to be marked if it will not dim rather than have specials that will dim. This means instead of 100 lumen per watt which LED's can produce, most bulbs are down to 70 lumen per watt.
The LED tubes to replace fluorescent are around 100 lumen per watt, but with the removal of wire wound ballasts from sale the fluorescent is around 95 lumen per watt and around the same life span and less than 1/4 of price to replace, however what the LED can do is produce less light, so a 5 foot fluorescent is 58W at around 5500 lumen and 5 foot LED 24W at 2400 lumen which is all well and good if you don't need 5500 lumen, but it is hardly a replacement will half the output, reason for half output is it will then work with the old wire wound ballast still in place, you just swap starter for a fuse, however the ballast is producing heat so although the tube give 100 lumen per watt the lamp as a whole is down to around 70 lumen per watt because of losses with the ballast.
We are seeing street lamps replaced with LED, I think maintenance is a large factor here, all the control gear is swapped every time we replace an LED which is wasteful but ensures when you swap it then it works, so semi-skilled people can swap the LED lamps, it needs a skilled man to swap the sodium lamp and ensure the control gear is OK, and also the LED light is better directed to where it is wanted, but my son tried swapping from fluorescent to LED at work, and had to go back due to complaints of not enough light. He also had problems of sensors on machines being triggered by the LED lamps, clearly they could be swapped, but when you look at cost of down time to swap them all it was a non starter.
I think the chances of a filament landing across the connections is slim, and if it did then it would likely ionise the gases in the bulb anyway, it's the ionisation which causes the short circuit not the filament. Often with ionisation it will produce a bright flash and coat inside of bulbs with a black deposit.
I suppose your now going to tell me bulbs don't produce light they suck in the dark and that's why the wick of a candle goes black and a bulb goes black when it fails, it has sucked in too much dark and is now full? And if you believe in dark suckers then you must be a sucker!
