Out-of-order execution and pipelining date back to the 1960s. The paper calls out the similarity: "If one views the blocks of this scheme as very complex instructions, then this architecture devolves to a pipelined architecture for executing those instruction, and the interlocks to prevent inter-instruction dependency violations."

In the late 1980s it was a common belief that the limit of single-core CPU performance was very near. So there was intense research into multi-core systems, the holy grail was to find a way to efficiently execute ordinary sequential programs. That was what this paper was trying to achieve: "While we currently believe that this work will lead to an architecture which can achieve factors of 10-100 times the performance of uniprocessors on unmodified Lisp programs, we have no proof, even in simulation".