I'm not sure exactly what these "filler pages" are called, so I couldn't do a proper search.
If I have a business, say a plumbing/heating company in NYC, and I created these HTML pages:
New-York-City-plumbing-company.html Manhattan-plumbing-company.html Brooklyn-plumbing-company.html New-York-City-heating-service.html Manhattan-heating-service.html Brooklyn-heating-service.html
and the content for each page type was the same, except the name of the city/neighborhood changed, i.e.
<h1>[Neighborhood] Plumbing Company</h1> <p>description of plumbing service</p> <h1>[Neighborhood] Heating Service</h1> <p>description of heating service</p>
Would this be helpful, harmful, or neutral in terms of SEO? I'm a little afraid Google might see that 95% of the content is the same, minus the name of the neighborhood, and punish my site for it.