Brian Lozier back in 2003 - Template Engines:
"I'm basically advocating a "template engine" that uses PHP code as it's native scripting language. I know, this has been done before. When I read about it, I thought simply, "what's the point?" After examining my co-worker's argument and implementing a template system that uses straight PHP code, but still achieves the ultimate goal of separation of business logic from presentation logic (and in 40 lines of code!), I have realized the advantages and honestly, can probably never go back."