There are two different issues at play here.
The number of writes that each cell can support is what it is. If you write to a cell, that write is used and cannot be reset. Do not worry about it. If you write to the drive all day long for five years you might have a problem.
The Secure Erase will deal with the issue that the drive keeps a list of available cells and writing to a cell takes it off that list. So after the full format, the drive may not know of any free cells and have to perform Garbage Collection to do any writes. This will result in s-l-o-w write performance. This performance degradation during normal usage is what the TRIM command addresses. Be sure to install Win7 with the drive controller set to AHCI mode so that the TRIM command will be passed through to the drive (this is a BIOS setting).
The list of free cells is reset by the Secure Erase, so the drive is "reset to factory state." The wear on the cells is what it is, and cannot be reset with current drives. The best solution is to ignore it.