Once you produce your video from Camtasia and upload it to Vimeo, you may get the following message:
This notice is just a warning. This does not mean your video will be blurry. In most cases you can safely ignore the message, continue to upload and end up with a high quality video. If you play the MP4 and it looks clear on your machine, then it will look clear on Vimeo. However, make sure that you click HD when viewing on Vimeo for best quality.