1. A method of operating a computer comprising the steps of: determining if speculative write prefetching is beneficial; sending a disk operation list having a write request to a disk drive; and speculatively prefetching data to service the write request if speculative write prefetching is determined to be beneficial wherein speculative prefetching includes: previously forming multiple disk operation lists having read/write requests; servicing the write requests of the previously formed disk operation lists; and comparing over a time period how often the write requests of the previously formed disk operation lists were serviced in-order versus how often the write requests were serviced out-of-order, speculative write prefetching only being enabled when write requests are serviced in-order more often than out-of-order.