I would use tiom/kiom in this way: "mi amas lin tiom, kiom da sablon la dezerto havas." Would that be correct/understandable?
The trouble is "da sablon" - because you would never have an n-noun after "da". Maybe something like ... tiom, kiom la dezerto havas sablon.
The preposition da does not take an accusative. The accuasitive is used with preposition only to distinguish locatioon and direction with those preposition which can give both:
en la domo – in the house (location)
en la domon – into the house (direction)
but: al la domo – to the house (direction, but the preposition al can give directions only)
Because there was a big fight about 70 years and tiom-kiom-ismo pretty much lost following an argument to Zamenhof's usage. As a result:
Kiom should (properly) be reserved for actual expressions of measurement or number, including with a da phrase.
This is one of the very few cases of prescriptive grammar in the language.
I had not heard of tiom-kiom-ismo (and I would love it if you could cite a source or link for the "70 years" number.) I do know, however, that it's possible to use tiom and kiom without da -- and for grades, so I decided to look for a source for tiom-kiom-ismo.
I found this (see link below.) I think you're mistaken. "Tiel granda" and "tiom granda" mean different things, but both are valid expressions.
Edit - let's degree to disagree - har har har. :-)
"Du malsanoj en Esperanto." It's not authoritative, but the arguments are clear and convincing to me. (The other malsano is using "kia" like "ol" and "kiel".)
I hesitate to just call a grammatical structure "emphatic" -infrequent structures usually emphasize some specific aspect of meaning. Substituting "kiom" emphasizes quantifiability, like when Z uses it: "
La propagando de Esperanto, kiom ajn grandaj estas ĝiaj lastaj progresoj, estas apenaŭ komencata."
De Hoog's observation is that Zamenhof scarcely ever did this and his main argument against tiom-kiom is that its popularity creates a style where it becomes hard to understand the limits of tiel-kiel, confuses new Esperantists, and departs from the Fundamento. Although it's a prescriptivist position, it doesn't say that comparisons and analogies with kiom are always wrong, only that they stretch the meaning of kiom and confuse the usage of kiel.
I think our disagreement is mostly in degree. I wouldn't introduce kiom as a more emphatic option when comparing degree. I'd say that it makes a quantitative metaphor - it denotes that someone could count or find a ruler or a scale - and that this sense is sometimes (rarely by Z) stretched to qualitative statements for rhetorical effect.
Thus I understand that, "kiom longa" is perfectly natural for measuring timber, "kiom granda" may be natural or stretched depending on the sense of "granda", "kiom aminda" is certainly silly - but poetry may benefit from silliness.
As jxetkubo alludes to in his later replies, "kiom" in place of "kiel" here does not precisely mean the same thing. There's a sense of "emphasis." That is, you're kind of saying "yes, I know the universe is huge, but how huge is it?" With "tiel" it's more neutral - like "what is the size of the universe."
Neniu scias kiel granda la tuta universo estas, sed la observebla universo estas proksimume 13.8 miliardoj lumjaroj.
Astronomiisto estas ĝusta vortfarado, sed la normala vorto por tiu profesio estas astronomo.
La respondo de "kia" gxenerale estas adektivo. La respondo al "kiel" estas adverbo.
Spaco estas granda. Tre granda. Vi ne kredos kiel vaste, grandege, mensogeme granda ĝi estas. mi intencas ke estas longa vojo sube la vojo al la apoteko, sed tio estas nur arakidoj kompare kun spaco.