I got one 6 cell pack to take about 1700mah out of its ratex 3300mah. By trikle charging it (0.1a) then discharging then trikle chargong at a higher rate 0.3 the. 1.0a).
Iv got some old really dead nicads ill try volt checking individual cells on just for practice

...before i stab into my "good" packs.
Ill try the agressive techniques after i try gently reviving them.
Exploding or venting cells suck. Had one pop on a nicd i melted when i was 12 and decided to try and take it apart to fix it....shorted and POP!!!.
Also blew up a bunch of AAs trying to build a 100,000v "shocker"