Redirection array iRule does not hit

My first question is whether redirecting to the subfolders is necessary. It'll kill SEO and is confusing from a usability point of view.

Is reflecting the subfolders a requirement or is it deemed a consequence of the migration?

I've dealt with a number of migrations where it was assumed that subfolders would be required and the customer acquiesced to using them. However, it's usually not necessary to change the URLs.