@jedaisoulSep 19.2016 — #Surely the question should be "Do we need to apply [b]different[/b] SEO strategies for different search engines?"
That assumes that you know how the search engines' algorithms differ, and, for on-page optimisation, which search bot is crawling the site. Do you? If not, the question is irrelevant!
@tidingstrongOct 28.2016 — #I presume it will depend on the site. But, from an expert point of view, you need to re-evaluate your strategy. A successful one will need to adapt to changes for the better.
@EugeneVOct 28.2016 — #Different algorithms = different strategies.
Plus each SE is unique and different by traffic. So you need to decide what should be main target and concentrate on it. That is recommended not to spread between different SE.