The original design featured a cord with a lot more plasticizer in the plastic, which was much more flexible. In reducing the wonky chemicals in the cord, the cord has become much stiffer, and this is fundamentally what causes the problem.
To have it disconnect less often, the cord must have a somewhat longer straight run across the tabletop into the power inlet. The shorter the cord, the more force you can place on the MagSafe by accident, and the more likely it is to disconnect.
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The suggestion that you take it to the store was based on the possibility that the magnet (which is in the computer, not the cord) was too weak compared to what it should be.