No - you'll have to ask the commenter a few notches above about that. I was referring the general distinction between the terms. In general - just because a phrase is easily understood doesn't mean it is idiomatically correct or natural-sounding to a native speaker.
As to the phrase itself: from my limited knowledge of the language, it does sound to be very close to correct -- so I'd be curious also as to what the sticking point is.
Not a native speaker, but it sounds almost spoken/informal in my mind. "Yucatan is a land (place/territory) - it's the one with the least land that I have seen."
Doesn't seem that weird to me, but I hear a pause before "la"- curious what makes you think it is.
Yes. The sentence in question is "Yucatán es una tierra la de menos tierra que yo he visto".
The section "la de menos tierra" sounds fine in isolation, as do the preceding and following sections.
But together they give off a very archaic feeling. Understandable since it was written almost 500 years ago.
A modern version, might be:
Yucatán es la tierra de/con menos tierra que (yo) he visto.
If you know Spanish and you read that sentence and the following ones here: https://www.wayeb.org/download/resources/landa.pdf (cmd+f or go to page 101) you'll notice that every single sentence is rendered differently as it would be in modern Spanish.
An example:
Yucatán es una tierra la de menos tierra que yo he visto, porque toda ella es una viva laja, y tiene a maravilla poca tierra, tanto que habrá pocas partes donde se pueda cavar un estado sin dar en grandes bancos de lajas muy grandes. La piedra no es muy buena para labores delicadas, porque es dura y tosca; empero, tal cual es, ha sido para que de ella hayan hecho la muchedumbre de edificios que en aquella tierra hay; es muy buena para cal, de que hay mucha, y es cosa maravillosa que sea tanta la fertilidad de esta tierra sobre las piedras y entre ellas.
And a quickly made conversion into modern Spanish, trying to preserve certain things while excising others haphazardly:
Yucatán es la tierra con menos tierra que yo he visto, porque toda ella es piedra viva, y tiene maravillosamente poca tierra, a tal grado que habrá pocas partes donde se pueda cavar (4-5 metros cuadrados) sin dar con grandes bancos de lajas muy grandes. La piedra no es muy buena para labores delicadas, porque es dura y tosca; pero, tal cual es, ha sido usada para construir los numerosos edificios que en aquella tierra hay; es muy buena para cal, de la cual hay mucha, y es cosa maravillosa que esta tierra sea tan fértil, sobre las piedras y entre ellas.
EDIT: so everything is understandable really, but some things, like the phrasal adverb (?) (locuciónes adverbial) "a maravilla" has become less used than using -mente to convert an adjective into an adverb. And some articles are used strangely, and some words aren't used anymore (estado as a unit of area), empero instead of pero, etc.
I'm glad I could help. And yes, I can see how it can be difficult to distinguish them, especially since there really wasn't any word that truly has become obsolete in those sentences, except the specific meaning of estado, it was just a matter of how everything works together, both words and phrases.
Also note that even in the modern version I made, some sentences sound formal, or perhaps literary, such as "que en aquella tierra hay" rather than the super informal "que hay allá" or the middle ground "que hay en aquella/esa tierra".
Also note that I completely botched the spelling of lucuciones adverbiales by adding an accent and eliding the plural, oops.
complete side note but is that what he would have said verbatim or a rendition in modern Spanish? super curious