i don't think i'd trust the tabs. do they really keep the tool on there? because it looks like they just let you mash it up against the cup as you're torquing on it. it doesn't look like there's anything to keep the tool from slipping off to the outside. i could be wrong though. i don't think i used that tool last time i futzed with that bottom bracket.

does that nifty tool that screws into the spindle and has another part that screws down onto whichever tool you're using (if that tool works with flat tools) to secure it in place work with that wrench? i think it's a var, or hozan tool.