Although genetic information is acquired only once, cultural information can be both abandoned and reacquired during an individual's lifetime. Therefore, cultural evolution will be determined not only by cultural traits' ability to spread but also by how good they are at sticking with an individual; however, the evolutionary consequences of this aspect of culture have not previously been explored.
The problem here is that this is totally mistaken. Genetic information - information in DNA - can also be abandoned and reacquired during an individual's lifetime. It is common for individuals to be infected with DNA-based pathogens on multiple occasions. Immunity doesn't always last - and often vaccinations need to be regularly repeated. Many parasites can attack the same host many times throughout that host's lifespan. Cold and flu viruses are familiar examples. For pathogens, success often depends on how good they are at sticking with their hosts. This is true for DNA-based pathogens - as well as cultural ones.
My estimate is that: 9 times out of 10 when academics play the game of picking the thing that makes cultural evolution different, they come up with answers that are just wrong. The differences between cultural and DNA-based evolution remain widely exaggerated. That is not to say that cultural evolution and organic evolution are exactly the same - just that wide-reuse of principles from the organic realm is possible. Often differences between the realms turn out to be quantitative - rather than qualitative.
Failure to appreciate the similarities between the realms leads to a failure to reuse existing work - and to pointlessly reinventing the wheel. A failure to appreciate the similarities between cultural and organic evolution is one of the most persistent problems for the field. Most scientists don't understand the similarities at all. Only a small percentage have got as far as understanding that both realms obey Darwinian rules.
You might think that this would lead to academics flaunting their understanding of the similarities - to demonstrate that they understand the topic. However, more often than not the temptation associated with detecting some difference - and then developing a theory about it - seems to be too powerful.