1. Data processing means for effecting data processing transactions according to programs of instructions including predecessor-successor pairs of instructions, a predecessor instruction having one or more successor instructions, a successor instruction having one or more predecessor instructions, said instruction having indices, said data processing means comprising: (a) first means for effecting the transaction of instruction execution components specifying operands and operators to produce execution results pertaining to further operands and operators, and execution completion signals pertaining to said execution results; (b) second means for effecting the transaction of instruction enable components specifying instruction execution sequencing to produce enable events pertaining to further instruction execution sequencing, and enable completion signals pertaining to said enable events; (c) associations of said execution components and said enable components, and associations of said execution completion signals and said enable completion signals having associations of indices corresponding to said instruction indices; (d) third means for the transmission of said enable completion signals from said second means to said first means, and for the transmission of said execution completion signals from said first means to said second means; (e) a transaction of a given execution component and a transaction of a given enable component occurring respectively in said first means and said second means, said given execution component and said given enable component having associated indices corresponding to a given instruction index; (f) a transaction of a given instruction being conditioned on the occurrence of completion signals generated by the transaction of certain predecessor and successor instructions of said given instruction; (g) transactions of said execution components subject to said enable completion signals, and transactions of said enable components subject to said execution completion signals being overlapped to occur freely and concurrently with respect to each other.