It is possible already - you can do `command 2>&4` to separate the output from one command in a pipeline into its own stream, then do `command2 <&4` to pull from the further down the pipeline.
This would allow many things, for example searching for multiple terms across all files in the whole file system in one go without opening each file more than once, and then grouping the different results together in accordance with the term that they matched.
