Yes, quite the opposite 
But I will admit to being as close to a moron as is possible on this topic, I have really no practical fighting skills as the last time I was in a fight was when I was eleven and another girl accused me of liking a boy I didn’t. Girl fights don’t count. So I think the class will be enlightening. A lot of it seems to be about awareness of one’s body in space and relative to the hurty bits of other people’s body coming at one. Not a bad thing to learn.
Hi Testy.
It sounds like you’ve been getting some pretty good stuff. With regards to the “don’t let them back on their feet” business, this really is sensible - no doubts about it - but you just have to watch yourself with the legalities.
Because of this, I prefer to emphasise an approach which means the assailant isn’t able or willing to get back up once you put him down. This means softening up with strikes and throwing them hard. I have a personal preference for the suplex/bodyslam style of throws which put them down pretty damn hard. Given a choice of smack then throw or throw then smack, it’s a no-brainer. Of course, smack-throw-smack may still be necessary, but I’d still look for the opportunity to leg it over the continuing the fight option.
Look for the knockout first, the throw second and it’s more likely that your opponent will stay down once put down, or failing that be less quick to get up and follow as you practise the ancient art of “flee-jutsu” 
Unfortunately, no martial art is safe from bad practitioners and teachers. Here’s some thoughts from Geoff Thompson regarding his experience in JJ:
“JJ tends to be too defensive, “when the opponent attacks we defend with…” etc…with few exceptions techniques are practised against designated attacks and with compliancy…many JJ practitioners tend to lean heavily to grappling…several of my friends have been stabbed by friends or girlfriends of the person they’re tied up with.”
He concludes this section by saying:
“I also find a lot of the JJ systems no longer include randori (free fighting), this is what takes the teeth out of it really, it they re-introduce this I think there would be a marked difference.”
Quotes taken from “Animal Day” by Geoff Thompson from Summersdale Publishing. Great reading for anyone interested in self defence.
Maybe your instructor put the teeth back into JJ. Geoff describes the majority experience in here though.
Idlewild, it sounds like what your studying has some of the classic markers of a “wishful thinking” approach to self defence. There’s absolutely nothing wrong with taking up a martial art for the fun, the exercise etc. If you really want to learn how to defend yourself should the fit hit the shan though, you may want to consider something else.
Should this be the case, perhaps you could post an account of your last training session beginning to end, so we can see what it is you’re doing before jumping to any conclusions.
Arts like Krav, Aikido and Systema focus on “awareness of body in space”-type concepts, and they have simply proved unworkable in real situations.
Dave
It seems that I’m talking about something different than the usual. JJ class almost always resulted in bruises, sprains, and the occasional “bent finger” and sparring was about a third of the class. Getting the wind knocked out of me was too common to notice and I was knocked unconscious several times as well.
I had always assumed that what I was taking was the general experience.
Alas, it seems that JJ has been reduced to stylized, defensive moves “with compliance” as the man says. It’s unwelcome news but thanks for reducing my ignorance on this.
Best regards
Testy
I appreciate your very informative input but I feel like I’m hijacking the thread a bit. I’m mostly doing it for fun and to lose weight - I do not believe that I belong in a fight and my approach remains to avoid situations where I’ll end up in one. Not that I devalue self defense and I applaud the OP for looking into it. Because obviously my approach has its limits.
I was being mildly facetious in the sentence about awareness of one’s body in space relative to other people’s hurty bits coming at you. Decode to “Oh look, someone’s trying to hit me, I should maybe move?” This was in relation to a drill involving trying to tag a partner’s shoulder while trying to block them tagging yours. I don’t know if it has any benefits for learning to defend oneself but it was definitely one of the most fun things I’ve done with clothes on.
Kudos for your contribution to the thread though! Very interesting and hopefully very helpful for the OP.
Idlewind:
Fair enough. One of the biggest mistakes people make when studying martial arts is thinking they’re getting one result, when in reality they are getting quite another. You seem to have your head screwed on straight about what you want and what you’re getting - more power to you
The shoulder tag thing is a useful exercise for beginner students too. It teaches you about staying in range of an attacker, dealing with what they’re trying to do whilst executing you’re own techniques. This helps to address the problem of running in, doing one technique then running away again, which is what a lot of beginners struggle to overcome.
Thanks for the compliment too