But then we have the Win 8 SSD "optimizer" function, which can be run on a RAID 0 volume of SSDs, at least it did on a RAID 0 array I have. But the question is, did it actually do anything.
Before this optimizer and Intel's RAID driver support for TRIM in RAID 0, Windows 7 sent TRIM instructions to RAID 0 arrays of SSDs, as it would to any SSD. The problem is the TRIM instructions never reached the SSDs, the RAID driver does not pass them to the SSDs.
The format of data stored in RAID 0 arrays is different than that of data stored on a single drive. The Windows file system sent TRIM instructions with file addresses it thinks the data that is no longer needed is located, which is not the same at all as where the data is actually stored on two or more SSDs in RAID 0. Apparently mapping those TRIM instructions to the actual multiple disk locations on the RAID array where the data is stored is (or was) very difficult, time and resource consuming, or impossible. So the TRIM instructions are simply ignored by the RAID software when the target disk volume is a RAID array, thus no TRIM for RAID volumes. In short, the RAID driver/software does not allow TRIM instructions to work.
The Win 8 optimizer may send TRIM instructions to a RAID volume, but what is different about this than the scenario I described above? Nothing. The Win 8 SSD Optimizer has been available for quite a while now, and I'm not hearing about the miracle of the Win 8 Optimizer causing TRIM to work with SSDs in RAID.
That can be tested with the trimcheck program, just Google on trimcheck and you'll get many download sources and descriptions about it. But I'm sure all you'll find it's not working for you on your Z68 chipset mother board, since Intel does not support RAID 0 TRIM on your board. But some people say that is an artificial constraint imposed by Intel (which basically is correct), and they have found ways around this.
You can find modified BIOS files that trick the Intel RAID system into believing it is working with the appropriate Intel chipset to allow TRIM in RAID 0. Those modified BIOS files change the chipset identification number, and may have a different (newer) Intel RAID Option ROM, since only IRST version 11 (and newer) Option ROMS and IRST drivers support RAID 0 TRIM.
AFAIK, the idea about EVO's not working in RAID was started in a forum post, where someone said he was told by "Samsung support" that EVO's won't work in RAID. It turns out that Samsung outsources their telephone support to another company, and the personnel are poorly trained, and best suited for "how do I turn on my PC" questions. IMO that "answer" was given just to end the conversation.