Considering that the two quantities are linked by reality, how can be both imposed by independent definitions?
I am aware that the change taking place next May does not effect common weighing in chemistry and engineering, but still the new definition of mole (an exact number of entities, to be called Avogadro number as well) does confuse me, conceptually.
Direct counting is not a practical way of sampling, so already I do not see the good of defining mole as a fixed number of entities (of course I have thought in this way already, but I am not a definition :).
How can I now weigh a mole of substance, in principle? It seems that without a history-of-science background, armed by the mass definition and mole definition, I cannot weigh in moles despite of having both very well defined.
Before, the "only" knowledge required was a table of atomic masses, and one could have done that even ignoring the value in grams for 1 amu, if not interested in spelling out the value of Avogadro number itself. I think is what happened before mass spectroscopy sort of techniques revealed the absolute mass of particles and atoms.
To date, the Mole is conceptually and mathematically linked to a mass measurement, ie. the amu and its multiples. With the new definition the two things are distincts, as 12 g of 12 Carbon is not a Mole anymore.
Please clarify without listing the non-operational pros of the new definitions, as the fact that the latter stresses the difference between matter as mass and matter as substance even more than before, to mention one that, as a chemist, I like much.
Edit after a comment:
The abstract of this paper by B. P. Leonard express my concerns in a more elegant way: https://iopscience.iop.org/issue/0026-1394/47/3