Yes other than JPJ I don't think anyone can do this for real.

It must suck to get various world records including a 40-yard dash time at age 18 that was within 0.11s of Usain Bolt's best time, and to do this ten years younger than the average age of a female world record-holding sprinter, and to do it while spent from track practice, and on her first try with no previous practice at the event, but still do it at a faster pace than the world record 50m female sprinter, and for there to be no record of it anywhere.
It's also peculiar in that in 100% of all cases, sprints both shorter and longer than 100m have slower speeds [because less time is spent at top speed for shorter sprints as you said, and in sprints over 100m, sprinters get progressively more tired].
But Jane is the one singular exception to this universal rule of sprint speeds - she is the only case in history, for as long as sprints have been recorded, where a higher m/s speed was achieved in a short sprint than the nearest world record in the same demographic.
...
But on a serious note:
When you realize how utterly moronic Jane's alleged 40-yard dash time is, then see how she was talking about "it" when she recounted "it" in her post, with how much specific detail she included about "it", it just makes me wonder how sad the person must must be behind the account.
Hulkotron - do you remember The Squadfather?
He claimed to be 230-lb at 5'11", which was would be assumed to be a pretty good size. Meanwhile, he was 330-lb at that height, and it seems possible to me that his early death was the result of his obesity. He was doxxed on here and had his mugshot photos posted, and was exposed as a fat man living in a trailer park.
During his time here, he was sure to make everyone feel small - most of whom were in better shape than he was.
I wonder what the state of a person is who feels the need to lie so extravagantly for a message board? And for Jane to be losing her mind when I said I got 12s to 12.5s in the 100m sprint makes me assume the person running that account isn't remotely fast. No one running 11.11s would even care about someone else claiming ~12.12s. Let alone a woman, where 11.11s would be the elite among the elite. That defensive reaction is that or a person who has never been close to such a time.
Add to this, the same MAN running the Walter Sobchak account is most likely JustPlaneJane.
And remember that Getbig Chicago area meet-up that never happened? JustPlaneJane posted that Walter Sobchak was 235-lb, then changed it to 245. And also claimed Walter Sobchak's girlfriend was 114-lb.
When you consider Krankenstein denied being there, you know that meet-up never happened. So Walter Sobchak used the JPJ account to a claim a 245-lb body weight and a 114-lb girlfriend...meanwhile, it never happened.
My assumption is that Walter Sobchak is another Squadfather, and can't post a picture due to either being ugly or obese - so has to concoct a story of being massive, with a petite girlfriend.
Even JustPlaneJane's claimed weight of 134-lb at 6'0". Does Walter Sobchak have no clue how skinny that is? Its 5-lb over the cutoff for anorexia in a woman!
My assumption - and I mean this sincerely:
The man running the Walter Sobchak account doesn't even know what fit women even weigh. So he made up JPJ's 134-lb weight and his fake girlfriend's 114-lb weight, which, IMO, exposes him as a person who doesn't get laid enough to even know what fit women weigh.
5'7" and 130-lb would be very fit/slim for a woman. 6'0" and 134-lb would be a stick. Yet JPJ claimed a 309-lb x 3 deadlift.
IMO, that would be about on par with a man my size [200] deadlifting about 650. It's not impossible - but very rare.
So my guess is that Walter Sobchak doesn't get laid much, thus having no idea what weights to claim for the made-up women he includes in his posts.
So I'd say he is an incel. And I don't say that to be a jerk...I'm just saying that we have now established the Walter/JPJ posts to be bullshit...and I think it's fair to say the person inventing the claims has no familiarity with what women actually weigh.
I talk to enough women to immediately find it strange for a woman alledging to be healthy to also claim a 134-lb weight at 6'0".
It just makes more sense to me that Walter Sobchak doesn't have many encounters with women, to make up such weights.
Again, I'm not saying that to be a jerk - I'm trying to neutrally think of reasons why those weights were chosen. IMO, it came from a man who doesn't talk much to women. I talk to enough women who check their weight at my house to know that 130-lb is about as thin as any healthy adult woman will be, unless she is under 5'7".
6'0" and 134-lb would be a stick, and no woman that size is deadlifting 309x3.
Also proof that JPJ isn't a top sprinter:
She said my 12.12s claim isn't believable because I have skinny legs. Any top sprinter would have trained with enough people to know many guys running 12.12s has legs my size or smaller. It's also the thought of a casual to even think in terms of leg SIZE. It's leg STRENGTH that matters, and my legs are strong for my size. More SIZE [weight] would in fact just bog me down. Having strong but SMALL legs would be a benefit.
Any top sprinter would be thinking in those terms. IMO, only a casual who WATCHES sprints would immediately think in terms of leg SIZE.
Also, if JPJ does indeed own the skinny legs he/she posted, she would have absolutely internalized, from HER OWN lived experience that leg size doesn't matter much.
How can a woman that skinny with legs that skinny but who supposedly runs that fast have ANY mindset other than being fully aware that skinny legs don't stop a person from being fast? I mean, JPJ's legs are sticks. So she should be the FIRST person to know that skinny legs are not a deal breaker for fast sprint speeds. Right?
But for "her" to doubt my [paltry] sprint claims on the basis of my having small legs is not the thought process of a woman with skinny legs who ran an 11.11s 100m.
This is why I believe it's a man running the JPJ account...and a man who doesn't know much about women. I'm not saying that to be petty - I think my reasons are sound. And just the absurdity of someone claiming to be a nearly anorexic woman deadlifting 309x3... 🤦♀️
Also, I'd be foaming at the mouth to prove my claims if I was getting called out as hard as JPJ is. No proof will EVER get posted by them, because it doesn't exist.
I should drop this topic now.

But let's just say: Squadfather made me feel like my 300 bench at 165-lb was nothing. He made fun of a 265x4 bench video I posted, and made me feel small. I think a lot of people feel crummy reading negative comments like that online.
Only to find out later that Squadfather was a morbidly obese fat fuck, and literally the least healthy person on this board. A man who likely DIED due to his obesity was making me feel like shit over claims that were a lie...
So yeah. That's why the JPJ stuff bugs me so much. To get trashed is one thing. But to be trashed by someone who is probably half my strength and fat...it just gets to me.
A lot of people feel like their accomplishments aren't good enough, because of losers like JPJ and Squadfather [RIP[.