Olive Oil and Architectural Preservation

York Minster
Is there a down side to using excessive amounts of olive oil on a building? Apparently, we're going to find out.
One of the most beautiful and revered cathedrals in Christendom, York Minster in northern England has survived war, looting, fire, pillaging and other threats over the centuries. But the Gothic masterpiece is crumbling due to a relatively recent enemy: acid rain. Preservationists, however, may have found a way to protect it using a common kitchen item.
The limestone rock used to build the church is vulnerable to acids, and has been under attack since the Industrial Revolution began filling the skies of England with acidic pollution, according to Gizmag.com. The result is acid rain that can wreak havoc on earthly structures.
And despite their best efforts, preservationists have found no protective coating that could keep the towering spires of York Minster safe, until they hit upon a novel treatment: olive oil
The extract contains oleic acid, a compound that can bind with the stone and protect it, according to Dr. Karen Wilson of the Cardiff School of Chemistry at Cardiff University in Wales.
This could, literally, save Western Civilization if it turns out to be a viable protectant. Half of Italy could end up covered in olive oil and it could lead to a resurgance in protecting critical elements of the world's transportation infrastructure as well. I would use this on bridges and roadways (while acknowledging that you don't want people driving through olive oil and spinning out) to increase their lifespan.