Regarding the content type distinction - the most I've written about it will be in here http://www.distilled.net/training/video-marketing-guide/ - chapter 4
I agree that there's not completely hard and fast distinctions in terms of keyword type - but there is a trend of user-intent and - for the vast majority of keywords, you can make a reasonable assumption about what the user wants. Whether or not they are convinced to reassess or shift their intent based on what they find is another question .
Your cat urine odor example is a good one. Like you say, this would be best served by a YouTube video that explains the process....and could also recommend products within that video.
However, assuming the user doesn't then either click through to your website - or do a branded search off the back of that video, the second level of their journey might be to search "cat odor removal spray." At this point, they know what they want and are clearly (rather than ambiguously) keen to purchase.
For such a keyword, You don't want YouTube to rank - you want your site to rank with a great landing page you can sell from and drive users there so you can retarget them if they don't convert. If you've decided that your landing page will be best served with a video explaining why your cat urine odor removal spray is the best - this video shouldn't be on YouTube - for the risk that users go to youtube.com rather than your site and likey therefore don't convert to sale. Additionally, the video snippet may help to improve your CTR.
In this "on landing page" video instance, a cat urine odor removal spray video that helps users who want to buy the stuff is probably not going to be much use if it just explains the process and reasons for using a spray, rather than actually selling the virtues of the production. Conversely, the video which just sells the virtues of the spray isn't really going to serve the needs of the user who searches "how to remove cat urine odor."
You can say that you don't think the videos need to be that different - but I can guarantee when you actually give it a go and test the stuff, you'll start to comprehend the nuances and see what kind of content performs best. Interesting - it shouldn't take much more budget to produce two cuts of a video - one more informational and one promotional, than it would to create just the one video. Any skilled editor could easily do both at the same time.
Competing against yourself is problematic in two instances - specific traffic to commercial pages ..and also if you're trying to build links using video.