Tree Shaped Tombstones - Quality Control?

Evansville Wisconsin is a very appealing little town in the south east corner of the state.  Lots of great architecture and very well preserved.  Oh, there's a bit of odd political vibe to the place, but to a casual visitor this is not apparent.  

The cemetery is on the outskirts of town and in general is well kept up.  But I did notice one "Tree Shaped Tombstone" that caught my eye and held it.

Actually a fairly commonplace specimen.  But let's zoom in closer....

Yikes!  That's a bit of a typo.  Due to weathering and some pesky light angle issues I can't quite tell when Mr. Robinson died but I must assume it was before his wife passed in December of 1916. I think we can also assume that there were no children around to take notice of this shoddy craftsmanship.

It makes me wonder just how the lettering was executed.  In many cases the tombstone would have been put up when the first spouse died, then the additional data added later.  Sometimes you see big blank spaces that one's imagination can freely populate with tales.  I figure there must have been some kind of portable cutting tool, probably powered given the clean nature of the cuts.  Did they have a little steam engine or some such?  Or would they actually take the stone down and carefully take it "back to the shop"?  With the various cranes and such that their trade involved this would have been possible.

So many of the early stone cutters were immigrants, especially from Italy.  Whether out on the grounds or back in the shop they might have been working from written notes.  And when doing crosswords I have occasionally heard from my wiee that my penmanship is imperfect.