As always, the answer for this question is yes and no. Yes, they can work, and no, not all will. For the ones that don't some were added as jokes, others by ignorant members, and others by members who's methods are simply different from most other people's methods. In order for a spell to work you must first believe it will work, and perhaps more then belief since you must know . If there is any doubt about it then it will not work. If you're casting it and thinking "this is ridiculous and silly" then you probably don't have enough faith for it to work.
have a look for info on creating and using sigils instead of spells, personal opinion is they overcomplicate things or they are based on levels where they will cause no true effect on physical reality, simplified procedures like sigils have a much greater chance at success especially if charged and released right.