Templater will rewrite expressions inside formulas when their parts are moved or stretched. This feature also works on horizontal resize.
Each formula is parsed and analyzed by Templater. On push, resize and cloning formulas are changed, duplicated and readjusted. Templater doesn't evaluate formula, it just rewrites its expressions.
On flushing Templater will go though all remaining [[equals]] tags and convert them into formulas.
Since Excel doesn't allow [[tag]], {{tag}} or <<tag>> expressions inside formula, this is a workaround for changing text into formula.
Merge cell require at least two cells to be defined.
Therefore template contains tag [[groups.description]] across two cells so that it's not duplicated on resize, but rather stretched.
Sheet can be removed with a resize(tags, 0) when tag is located within a sheet tab or it has special :sheet or :page metadata. Still, formulas referencing that sheet will continue working, as sheet is not really removed, just special very hidden visibility is set on it.