I personally started off by playing only Sng when i first started to play. My ROI rate is around 38% so I do consider myself a abover average to Good Sng player. I do not bring this up to brag but to give you my personal point of view.

I have always found SNG very easy. This is especially true at the 5$ - 20$ range. I belive this sytem over complicates SNG strategy for your basic recreational player.
I believe the best SNG strategy is to play basic ABC poker in the early stages of these tournies. Basically, bring your big guns to war philosophy. When a BIG pot is played make sure you have the best hand. If you play this style you should not be involved in a lot of pots and by the time 4 or 5 players remain your tight image will allow you to begin to steal several blinds.
one thing I o believe in once you steal enough blinds that several good players may disagree (feel free to express your agreement or disagreement) is i believe in freerolling a hand. What I mean by this is allow your money to get in bad. Calling a short stacked all in with 8-3 against someones AK is a little worse than 60-40 underdog. If you play solid enough at the begining of the SNG and steal several little pots you should have enough to be able to call short stack all ins with cards that are not so premium putting it nicely.

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Kickboyswoop