As far as I know, none of the battery matchers suggest to use it.
Pulse/Flex, even with NiCd's most only said to use it every once in awhile.
But, on the other hand, there are several new chargers that use "Multi-Phase" charging where they vary the charge rates during the chrage process.
The Integy 16x5 & 16x9's stop charging every min for around 5 sec. then start again.
I guess in a way, there are several chagers that still do it, just the duty cycle is much longer compared to the older FLEX method.
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