As that would sort by the second column only, it would fail to yield the desired output in case the input was sorted differently.  For example, if all the rows with "2" in the first column came first in the input, the output would be

2,64,1.4.5,1.4.6,44642850,44642850,0,25828,9548,40128,1488095,761904.6
+4
1,64,1.4.5,1.4.6,44642850,44642850,0,27348,10028,59188,1488095,761904.
+64
2,128,1.4.5,1.4.6,25337850,25337850,0,27936,10796,28696,844595,864865.
+28
1,128,1.4.5,1.4.6,25337850,25337850,0,19236,10276,28196,844595,864865.
+28
...
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