Is it a game strategy or should it be classified as cheating?
Unfortunately using this dirty trick in poker is legal and not against the rules. Few days ago I found an article about all the tricks and how you can prevent the "angle shooter" to use them in the game. I think it is a really sensitive matter, we are talking about.
Check the whole article* and come back to see an example of "angle shoot", which went around the world!
... and here the example* : Video of the European Poker Tour Grand Final in Madrid in 2011
* Source: http://www.pokernews.com;www.youtube.com
