"bullcrap" Ok, let's get technical...
Current/electricity is lazy...
it will take the easiest route with the less resistance. The plug and play connectors add resistance. The more resistance in a circuit the harder it is for electricity to pass through it. Now if you remove the resitance, you increase the amount of electricity than can pass through your circuit.
So, if this fix did not work for you, it doesn't mean that it doesn't. If your DDE's still have a cold start problem then you might want to either replace your ballast or purchase a high output one.
Downside to a high output ballast is that it reduces the life of your DDE's by pretty much half!
And also, 3twent8i, please read this:
Originally Posted by Komodo
United Bimmer Do-It-Yourself Disclaimer: The following tutorial is meant as a guide and is not guaranteed to be complete or 100% accurate. By following this DIY, you understand any work done on your car is at your own risk and we hold no responsibility if you break something. If you feel uneasy with this risk, we recommend you take your car to a professional mechanic to have the work done. Otherwise, enjoy yourself and good luck!
PS: Did you solder them and slapped some shrink tape on them?