You have to be careful to only use a couple specific "devices" for NimH batteries. I forget which ones at the moment and I'm at work so I can't go look. But if you use only those allowed devices on NimH, you're good to go.
I've charged many a NimH battery on my Alpha-4 and it works just fine. Evidently, the Alpha-4 is precise enough that it can determine the smaller Delta-V drop of NimH batteries very reliably which says a lot for the programming and quality of the charger.
But again, you should only use a couple of the devices for NimH batteries, and those were named in the FAQ on the Litco site, although I think it (the FAQ or even the entire site) may be gone by now.

The diffulty of slow "cycling" (discharging) isn't the issue because the charger (any charger) simply looks for a certain voltage reading to stop the discharge.
The problem can come in the charging portion at the full charge point because of the flatter Delta-V of a NimH battery when done with a slow charge as I explained earlier. I would continue to charge at the 1amp rate with the Alpha-4 for that reason.
However, I have charged NimH batteries at lower rates and the Alpha-4 seems to detect the Delta-V just fine as far as I can tell, yet another testimony of the programming and quality of the Alpha-4.