In the dark ages, I've charged NiCd and NiMH batteries with a timer.
It's a good way *IF* you know the capacity of the battery and the
state of charge. Capacity is easy as it's in the spec sheet. However,
a given battery can have radically different capacity values at
different charge/discharge rates. To make the numbers look huge,
manufacturers use a slow discharge rate. The battery also has a
charging efficiency, where it takes more coulombs to charge the
battery, than it can deliver. I use 75% for most batteries. Once you
know all that, and the state of charge, you can calculate how long
you need to charge the battery. If the battery gets warm at the end,
you're overcharging and have probably killed the battery.

This is one of those rare cases where I have to disagree with Mr Lieberman.
How warm is warm? "Getting warm" is an indication that charging is complete,
or near-complete.

Many NiMH manufacturers claim their cells need to be "slammed" to get maximum
charge. I'm reluctant to do this. However, I've charged NiMH cells in those
"15-minute" chargers, and though the cells got hot, they were not destroyed.
(I no longer do this. I have about 20 cells of 2500mAh and higher capacity, so
I never need a quick charge.)

The best way to charge batteries is with a charger that lets you set the
charge rate, and watches for the signs that indicate the cell is charged, such
as the MAHA C9000. I generally charge at 0.3C or 0.4C, which is considered on
the low side for NiMH cells. Contrary to what Battery University claims, I've
never had problems with the cells overheating, or the charger failing to halt
at around 1.42 to 1.45 volts. (Note that his gripes are principally directed
at "consumer" chargers.)

The C9000 displays the battery voltage, so I can choose to stop charger at
whatever voltage I feel comfortable with. I'm not stupid enough to let any
charger operate without checking it occasionally. If you like, stick a timer
on the charger to shut it off.