No that is not correct. TRIM will work as well in IDE as AHCI mode. The only thing that benfits from running in AHCI apart from a slight speed improvement is the ability to Hot Swap the drives.
I revisited this and I may or may not have been wrong. I found no reliable source of info on this subject. I was always under the assumption that it was required because Win7 requires the MSAHCI driver to allow passing of the TRIM commands. Intel's 9.6 driver also allows passing the TRIM command. This can be found everywhere on the net. I may have interpreted this wrong. It may only mean if you are running in AHCI mode trim will not function if your not using the MSAHCI driver not that IDE mode lacks support for TRIM. If trim does work in IDE mode why is there no info on the net saying you must use the IDE driver included in windows 7. IDE drivers from the chipset manufacturer would surely need to support passing the trim command same as AHCI drivers. As far as the C:\Windows\system32>fsutil behavior query disabledeletenotify outputting 0. It does not prove trim is working it just proves it may be working.
Lets say TRIM works in either mode. Why cripple SSD performance by running in IDE mode. AHCI mode makes a big difference in performance in the testing I have done. See screen shots.
If anyone can come up with reliable info on this subject please post links! Reliable meaning from MS, Intel, AMD or a SSD manufacturer. BTW I'm talking native Windows 7 TRIM not a manual Trim tool.
Bill