JK> In a highly
JK> concentrated state, there doesn't seem to be a place
JK> for deliberation and reasoned reflection.
I would translate "vitakka" and "vicara" as "reasoning" and "study".
Vitakka shifts to the object with the help of the logical analysis of
the designations, and vicara investigates the object on the basis of
its concept. There's surely a place for those processes in the first
jhana.
The rendering 'applied and sustained thought' shows the consequential
roles that vitakka and vicara play, yet it removes the exact meanings
of these processes.