Depending on the details, I'd wonder if you'd just end up pulling in a single cache line from the row, regardless of how wide the row is. Even in his benchmark,

Depending on the details, I'd wonder if you'd just end up pulling in a single cache line from the row, regardless of how wide the row is. Even in his benchmark, you're wasting a good 5/6ths of the memory bandwidth you're using (pulling a 24 byte row and only examining 4 bytes of it).