[AdvantageEnglish]

I don't think that schools creating in-house texts is Reinventing The Wheel any more than any other textbook written today is a reinvention of the aforementioned wheel.

If a school uses trained, experienced teachers who create interesting topics and quality material - They can run educational programs that are one of a kind. Putting these ideas together into a text can allow the program to be implemented by all staff, creating a standard, reliable program throughout all classes in all schools within the company.

Of course, using off the shelf texts can also allow for uniformity and consistency.

It's a question of whether or not the school wants bragging rights for having a unique program used only by that school.

If the program is better than or at least equal in quality to anything else on the market at the time - it's time well spent.

Finally... 'Professional Books' usually have larger budgets which allow for nicer presentation, colour, glossy pages, accompanying activity books, cds, videos, teachers' guides, blackline master activities, accompanying web pages, posters, flashcards, ...so in my school, we've looked around and chosen the best off the shelf series for our needs and it works fine for us.