Variation Analysis and Positional Thinking

It is said that when choosing your move in sharp positions you should calculate all the tactical sequences - both for you and your opponent, in sufficient depth so that the position becomes not sharp; in positions where there are no tactical sequences, you should rely on general principles, positional understanding and overall game strategy (including proper piece placement and repositioning).

According to your chess experience, is that practically enough? Or is it only a time saving algorithm that omits excessive analysis? Or is it too much and unnecessary?

I think you mean in a tactically full position, one should analyze the position until it is not "tactically full" any longer? If so, then it really depends on the position for me. If I see an advantage, I'll try to trade pieces. If I don't see an advantage, then I'll avoid trading.