Meanwhile, another addition to our fine collection of doggerel, prompted by an episode of Renovation Realities and a rather hapless couple:
Shim shimanee, shim shimanee, shim shim sharail.
A shim's what you use when your measurements fail.
Shim shimanee, shim shimanee, shim shim sharoo.
With luck this won't fall when the reno is through.
And always cut once, after measurements two.