1. An apparatus for inserting one or more data bytes into a stream of data words, comprising: a first circuit to generate a first and a second intermediate data word correspondingly containing first and second zero or more data bytes of a first data word of a preceding cycle, said first and second zero or more data bytes being data bytes that precede and follow a first data byte insertion point of the preceding cycle respectively, and said first and second zero or more data bytes being repositioned within said first and second intermediate data words respectively, with said first zero or more data bytes being repositioned within said first intermediate data word relative to cascaded alignment impact of cycles prior to said preceding cycle, and said second zero or more data bytes being repositioned within said second intermediate data word relative to said cascaded alignment impact of cycles prior to said preceding cycle, said first data byte insertion point of the preceding cycle, and a first number of data bytes inserted after said first data byte insertion point of the preceding cycle; a second circuit to generate a first re-aligned variant of a first insertion data word containing said first number of data bytes inserted during said preceding cycle; and a third circuit coupled to said first and second circuits to generate an output data word conditionally using selected parts of said first and second intermediate data words, and said first re-aligned variant of the first insertion data word.