Hmmm. I'm fairly new myself, but i have studied and studied this battery thing.
First, as had already been pointed out you overcharged those batteries.
Second; I too use the Hobbico quick charger, WITH a PC power supply. Properly used AND monitored it will work for you. I e-mailed the RCBattery clinic in my research. They arent fond of the charger you and I use but for the opposite reason, it tends to UNDER charge NiMH batteries. Which leads us to reset and charge again...

That said, I NEVER charge at over 600mA and I'm running a 2700mAh battery. Here is my procedure, it may not be perfect but it has worked well for me:

After flying when I can be home to monitor it I set up the charger for a "quick Charge". I run it at up to 600mA for this charge, (Once in a while if I know the battery is real close to dead I will go as high as 800, but the one time I went a full amp I nearly cooked the battery.) While it is charging I periodically check the pack temperature by touch. Now Red told me a NiMH WILL get warm when it is close to fully charged, but should NEVER EVER be allowed to get hot, as this can ruin it.

If the pack is not warm after the 2 hour cycle shuts off, or if it peaks before that and the pack is still cold I will reset it, drop the current to 400 or less and charge cycle again.
Once I am satisfied I have it nearly fully charged, or if I need to leave for any length of time, I shut it all down and unplug the pack from the charger.

I then leave it all until the night before I am flying. the night before I fly, IF it has been more than 24 hours since I charged up, I will set up the charger at minimum current (200mA) and closely monitor the pack. I shut it off as soon as the pack begins to warm above room temp. I can live with a 90-95% charge versus a full charge.

Meanwhile I use the wall wart that came with the DX6i for the TX batteries, again monitoring them until they are warm, NOT HOT.

This has worked well for me, however the following should be noted:

I fly an H9 Arrow. Its a sport capable trainer, but its electronics don't have a really high draw.

I have NEVER been forced to quit flying early due to battery pack s being low.
I did leave one day when I felt it was too low for more than one more flight, I have since learned I had plenty. But I am superstitious, if I cant get in two or more flights I wont take the last one. I have witnessed too many aircraft getting re-kitted from just one more / one last flight.

I have been at the field for a full day, and gotten 6 or more full 15 minute flights out of my batteries, and still had some left at the end of the day.