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The shellac probably does slow the curing time of the BLO, but there's no harmful effects from it. You mention "dimensionally stable", remember that any film formed by BLO is very thin, and very weak. Coating the BLO after as little as 24 hours just hasn't proven to be a problem IME.
I started with absolutely nothing. Now, thanks to years of hard work, careful planning, and perseverance, I find I still have most of it left.
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Everything Fred said. Shellac over BLO has been used forever and is a reliable finish schedule. The key with BLO is to wipe it off completely. Better still is to avoid flooding it on in the first place. All that's needed is a wipe of the stuff to do the job of highlighting and adding color to the grain. Wipe it on, wipe it off. Done. You can read several articles from pro finishers that never wait more than 24 yours, and often much less, before moving on to applying shellac. Waiting certainly doesn't hurt but it's not a necessity for a durable finish.
BLO + shellac on woods like unsteamed black walnut is a thing of beauty.
John