PP.
\\\It is not exactly rocket science:
the drug blocks the reabsorption of sodium in the kidney and this drags water with it. \\\
Not so....not so. it may be simple to you, but to me and others it is a little more complicated.
You have mentioned just ONE type of diuretics, the thiazides, the "old fashioned" diuretics.
There are at least 5 groups of diuretics in this modern era, all with differing actions.
You are much brighter than me, but to say that it is not "rocket science" trivialises the OP.