I use a massive 60cm breaker bar (plus adapter) with a Park Tools bottom bracket tool. Overkill yes, but worked wonders on a siezed bottom bracket.
If you use the right bolt/washer combination, locking the tool in place and using a socket can be done. I use a crank bolt and a penny washer (the hole in the tool is quite big) without too much trouble. Glad you got yours out though.My problem wasn't the length of my bar, I have a 3 feet long torque wrench for when things get drastic, but the length of the actual adaptor that slots into the BB ring. Being longer than the one in your picture it kept canting over and slipping out of the slots when I applied lots of pressure on it. Because I was using a socket I was not able to screw a bolt through the tool into the BB spindle to lock it in place. Anyway, I got there in the end!
Could you explain what you mean about the crank bolt and penny washer - don't quite understand how this works - got any pics?If you use the right bolt/washer combination, locking the tool in place and using a socket can be done. I use a crank bolt and a penny washer (the hole in the tool is quite big) without too much trouble. Glad you got yours out though.