With Peach turnips that are thrown backwards go further than turnips that are thrown facing forwards. Yes this is using smash/cstick throws. You can use this to your advantage using something similar to a pivot fsmash as marth. If you dashback/pivot to turnip throw in the opposite direction of your dash you can get the increased distance of the backwards turnip pull. This is something I have not been able to find on the internet besides my post on reddit and it revolutionizes the way standing turnips can be used. I try to show the increased distance in this video. I get a mix of weak throws, smash throws, and then dashback turnip throws.
https://www.youtube.com/watch?v=Uaa8saXN5B4. This is applicable in any situation you are throwing a standing turnip, and it is very simple. To accomplish this literally just dash back and cstick in the direction you want your turnip to go.
This... is actually something that is not written in my guide and something I haven't heard of or seen before.
It looks very similar to existing known tech but its very subtle in how it is different. When I first saw it, my reaction was underwhelming, but then it was your description that made me realise that this is something else:
'To accomplish this literally just dash back and cstick in the direction you want your turnip to go'
To clarify we know of 3 ways of doing a reverse back throw currently:
1. Shield stop - > Shield throw: While running in a direction you cancel your run with shield then throw backwards
2. Jump Canceled Throw: While running, jump and immediately cancel with turnip throw
3. Pivot: Back throw turnip in the same manner one would pivot fsmash
What you're describing is something a little bit different than the above. After testing it myself I found a way to improve it a bit as well:
It seems that you can throw an item during the initial dash phase. This is kinda cool, but a super fast Jump Canceled throw can accomplish the same thing, except its much tougher to do and with the jump component, its likely to be marginally slower.
However I found that the regular turning-on-the-spot animation can be canceled in a reverse throw as well, effectively doing exactly the same thing but without losing any distance through the dash and shaving a few frames off as well.
While this mechanic is very likely to be known by frame wizards like Magus and Splits, I have not heard of anyone combining the fact that back throw turnip goes further than forward throw and the fact you can cancel your turn with a turnip throw.
Ergo, as far as I'm concerned, this is new Peach tech. And strangely enough, very applicable, especially vs Marth.
In any situation where a standing smash throw would be used to cover horizontal space, there is basically no reason to ever not do this.
Because this can be so easily confused with the other turnip options, I'd suggest 'extended (turnip) throw' as the name of the technique.