Well my client wants to rank for multiple cities which are in near proximity of the capital he is located in. I've suggested him to make a landing page for each region which he has agreed to. However, I told him to write a unique piece of text of ~400+ words for each landing page. What he has done though, is to write a single article in which he proposes to simply replace CITYNAME with the current region of the landing page. I have my doubts about this seeing as he very well could get penalized for duplicate content if he was to produce 20 landing pages, all being identical with the city replaced as the only thing. What are your thoughts on this? Doesn't it sound like a bad idea?