The ground game completely changes when brought out to the street. It's not the wisest place to be.
No arguements with that here. I like the "Street Grappling training priority" list Morne wrote above, and the fact that he placed escapes and getting back up to your feet as #1.
For starters, your foe may have friends that will stomp on your head as you try to apply one of those fancy locks or chokes.
True, but then, grappling is not all on the ground. Having a solid clinch game and the ability to move an attacker where he doesn't want to be moved - in between you and his friends coming to help, for example is a great skill to have.
Should the fight go to the ground, my goal is to keep top position, where I always have the option to disengage, give him a boot to the head on the way up, and run away or start dealing with his friends. While grappling is my favorite part of combat training, I train all the ranges, and my preference doesn't make me blind to the necessity of different tactics in different circumstances and environments.
Second, you lose the peripheral view of your foe. Your foe may be carrying a knife, a box cutter, or an ice pick for all you know. As you roll with him on the ground you probably wont see him grab for a weapon. Your side and kidneys are great targets for his blade. I'm sure you'll let go of your foe after you get shived.
Good point, the blade changes the game in a big way. The mere possibility of a weapon being introduced after the fight goes to the ground makes "killing" or immobilizing the opponent's arms becomes a much higher priority. There are some positions that BJJ black belts (and other high level guys from various styles) can put a person in, where it's pretty much impossible for the guy on the bottom to bite them, gouge them, or reach for a weapon with either hand. I'm not saying I could do it to any guy on the street, but there are definitely people who can. Sucks to be on the bottom vs. that guy, doesn't matter if you have a grenade in your pocket - it won't do you any good.
Also, who's to say the grappler doesn't have a knife as well, and is able to use his positional dominance to use it more effectively than his less skilled opponent? That's something that is usually overlooked when the "what if he has a knife" question is brought up. It's really the same as the other "dirty tactics" scenarios. They say "I'll bite the grappler", but the grappler can also bite you, and you're in his world. They say "I'll grab the grappler's balls", but the grappler can grab your balls, and you're in his world. They say, "I'll pull my knife on the grappler"...but the grappler might also have a knife, and now you're in...you get the idea.

Third, concrete isn't the most condusive place for ground mobility. Also, its going to hurt like hell or worse if you miss a shoot or get unbalanced yourself by a mis-throw and fall to ground instead of your foe.
If you are good at throws or even high impact takedowns, the concrete can be your best friend. I've heard it affectionately called "cement poisoning", and it's a fight ender.
As far as wrestling and rolling around on concrete goes, I’ve done it before. It's very uncomfortable afterwards, but you don't feel the pain nearly as much as you'd think when your adrenaline is up.
Personally, I feel its great to train ground work. It's always good to train in the possiblilities of a fight, but its not the cure-all that sport fighting and many MMA schools profess it to be.
Agreed, completely.
Also, it's a poor training habit to make grappling your first answer. Due to muscle memory, your body will try to react in a real fight with grappling.
I don't think anyone is advocating that grappling should be your first answer to a threat. There are a long list of things that have broken down before it comes to the fight going to the ground. I disagree that muscle memory will take over to the point where I will automatically choose the wrong tactic for the wrong situation, especially if I have cross-trained. Bo Jackson played both football and baseball – I’m not sure which was his favorite, but I doubt he ever tried to tackle the first baseman. The pitcher, maybe, but not the first baseman.
