I've been studying and practicing Judo for 20 years, and Ninjutsu for 13years, respectively.
In the 30 years that I've been on this earth, I've used the techniques numerous times in competition, with success. So, I know it works in competition.
In the last 15 years of my life now, I've used my skill, maybe 5 times, "off the mat". The other guy didn't have his way with me, so from that standpoint I'd say it works...to a certain degree.
If you're a lock/hold/submission guy, or a throw and counter ground person, fighting in the street is always going to be difficult when you go up against someone who throws things...i.e.; fists, bricks, sign posts.
This revelation has made me look at learning to throw my soup mixers, with a little more behind them. BUT...then I remembered, when you get older, most people in Cali are more likely to throw HPs at you.
Best bet for my age and AO = don't start nothin won't be nothin.
If push comes to shove, I can still dance.