Maybe we're using different documentation. In my company MSA is Minimum Sector/Safe Altitude. It gives you a safe altitude within 25nm of an approach navaid.
For enroute use, we have other official and/or company calculated min altitudes.
I am not familiar with SSA. Is it a "Jeppesen-altitude"?
BTW: All minimum altitudes should be corrected for low temperatures (and wind if in mountainous terrain), regardless of company policy. When it's cold you are lower than indicated altitude. If you forget this, you might get some unpleasant surprises.
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"Recovery was marginal..."