You can to some degree if you tweak it extensively. What I've done in the past is drop the framerate to 10FPS. this will produce some choppiness in the video but it's not that bad. If you go to 15 it's actually quite good but for my purposes I was trying to achieve the lowest bitrate possible and still have a large resolution. The less frames you have the less bitrate you need to keep the artifacts out of it. I prefer some chopiness over artifacts anyday.
Encoding using WMV I was able to use a resolution of 320x180, original was 16:9 aspect hence the odd resolution. Audio was set to 20kbps Mono. I only needed 50kbps for the video to keep atifacts to a bare minimum. Overall was 70kbps, considering the bitrate not bad at all and it will almost stream on a 56k dial up connection.