Troubleshooting a slow connection

A few days ago, my newly configured wireless internet connection has slowed. Since I've networked my PC to Weng's PC on my own (hambugera! daw...hahaha), I'm embarassed to call a PLDT technician expecting that I'd get scolded for messing up the connection. So the next sensible thing I did was to search the internet and voila! I found this article. It says changing my WiFi channel number could be the answer to my trouble...and....it worked!:) According to the article, a WiFi network that shares a channel with another network shares resources for "network connectivity" using up more bandwidth thereby slowing the connection. Honestly, I'm not sure that what I did improved my connection  (i've downloaded this utility that checks whether the channel i'm using is crowded with other wifi routers. none of the channels are even used in our area) but who cares?:)