We've all seen solo spins, either we are the ones spinning or our competitors. I know it happens and there a lot of variables involved, but  I feel that most can be prevented.

You say why, I practiced a ton of laps and still spun....?

You need to practice the "what if's"

What if there is a brake check in T1 as there often is
What if I clip the apron exiting T2
What if I get forced into a 3 wide and I'm on the outside
What if I get stuck on the wall (yea, they said don't pull off, but how then do I get off it)
What if someone gets loose exiting T2\4 and you have to lift suddenly just as you're getting back to full gas?
What if...etc.....

Here's the deal...about a year and a half ago in a league race, N4...Loudon and yes, I know the date...LOL I had someone check on me in T1 and I looped it....Personally...to me, it was embarrassing that I alone, lost control of my car and caused a caution,.

I set out to not do that again and it's paid off for me , that was my last solo spin! I can honestly say that. While it's true that I've got loose many a time and probably disrupted the flow behind me a time or two...I haven't looped it again...

Here's what I did...

I'd practice normally for a race, IE...getting the feel of the track, line, traffic, etc...

Then I'd pretend there was an abnormal brake check at a bad place on the track...requiring me to do the same...
Most times...you'll get loose and loop it...BUT after you do this a few times...You will start to realize what you can do to keep the car in control...gas, brake...a combo of both...each situation is different of course, but you get a general car control feel for it
I'd run into a corner hard and just let off the gas, sometimes braking hard...just to see what happens and how I could keep control regardless!

I'd clip the aprons entering\exiting the corners...I know I actually do this from time to time, but when I do..I know what the result of the car will be....In our prerace practices, you'll see me doing this type of stupid stuff...but there's a reason..<G>

Clip the grass at the cookie cutters...if you know the general reaction of the car with that setup, you will be able to save yourself more than you realize....

I'd turn the ai's down a notch or two so that I'd practally run over them, but I wouldn't. Instead, I'd run laps trying to get as close as I could to them without punting...driving in hard to see how to avoid if need be...
With them this low..it also makes for good "outside" practice...running laps on the highline....every track has one and you should be able to run laps up there without hitting the wall or cars....I've seen a bunch of cars (other leagues too) that will let a car pass, only to get out of shape on the highside as they are lifting....

Any of this making sense? More\less, you gotta practice for the stuff that probably won't happen, BUT COULD!

I'm telling you...after a bit of doing this...you'd be surprised how much trouble you can avoid by simply knowing little things to do to control your car....

An example of any of this would be Darlington,..I know that if I hit a particular spot of the apron exiting T2, I have to lift or shoot to the wall....1 foot to the right and I could stay full throttle....similar deal in T3....

Find out how fast you can go around the corner on the apron, IN CONTROL
You never know when you'll be forced or just simply find yourself there....too many times, I've seen cars get down there for whatever reason and wash up onto the track...bad thing sometimes...:(

I'd practice my line as if there were a car on the outside of me and I'd have to adjust to keep it low and not wash up....

You should get what I'm saying...and it really did help me to gain better car control even if it does sound silly...