I didn't. (Who said anything about NEC?)
My understanding is that the first Nexperia-based DVD writers were the DW800A series. Some earlier drives used Philips chipsets, but I don't recall them ever being publically branded as Nexperia. In any case, these earlier 4x & 8X drives certainly don't have the features we associate with the DW8xx & DW16xx Nexperia drives.
Regarding the offset, I just looked it up in database. It is a quick and, when interpreted correctly, pretty reliable way of identifying which chipset a drive uses.
The HP 300c is +1292 and all of the 'real' Nexperia-based drives I can think of have an offset of +618 (including the super rare SPD7000P Blu-ray writer). As +1292 is not a multiple of +618 (but we know from other sources that these are Philips-based drives), we can reasonably conclude that it is a substantially different chipset family.
Only if the drives needed them. A drive which could, at least in part, be self-calibrating would be much cheaper to produce. Paying humans to run the software through all those tests for every drive manufactured would have been very expensive.
Lite-On didn't release these tools. They were developed and released (concurrently with the drives they are intended for) by Lite-On employees.