So the basics of the idea is to have a tool that can automatically determine the playback position of a sample and, with a single shortcut, slice and produce a note at the cursor position in the song.
This takes the pain out of that particular workflow and makes it easy to e.g. replace a few bars with something else.
So it wouldn’t auto slice a big wave file according to pattern lengths in the project, slicing & placing note-events in the pattern editor at every pattern start (something which the track freeze tool does; https://forum.renoise.com/t/new-tool-2-7-2-8-track-freezing/32936 ), but be more of a manual thing? Cool B), but imo auto-slicing according to pattern edges (optionally be able to set the amount of patterns) and or sub divisions (bars) would even be handier. I guess this would only really work if you know the renders original bpm, the beats align in the new project, otherwise you’d still need to apply some manual sample editor finetuning getting the render to process right.
Maybe you can hack the phrasemate tool to auto slice a big ass wave into multiple phrase instruments and automatically place them into the patterns like dblue’s slices to pattern tool 
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