Inline filament dryer ?!

I tried to find some nice mods other people use on their printers.
And one of my finds was home made machine turning old plastic bottles into filament, with quite accurate results.
But the creator pointed out that in order to make it happen those bottles need to be cleaned and dried properly.
Towards the end he talked about his upcoming inline filament dryer.
Basically a thin ID copper tube (about 2m long) with heater cartridges for a soldering iron placed along it.
A tiny compressor blows dry air from the outgoing end through the tube.
He claimed it is able to get otherwise unprintable filament dry enough directly from the spool.
He did not specify though how fast his printer can print.

Problem is that post was from over 6 years ago and I can’t find the user or anything related to it.
The logic behind seems somewhat plausible.
A single strand of filament in a hot air flow and kept hot enough will dry much faster than a tight wound spool.
It could be a game changer for all those in rather humid climate zones.
One thing though I do wonder about - transporting the filament.
We need rather high temps to dry filament - close or at the softening temp of the material.
The AMS pushing would mean deformation is possible, same for pulling the filament.
But for the external feeder from a free rolling spool it should work.

Any thoughts, ideas or clue if someone tried an inline dryer ?
Some of my old printers might have been slow enough to dry filament on the go, but at my average print speed of around 350-450mm/s for PLA I doubt it would work.
Tempted though to consider the concept as an addition to a filament rewinder.
Refills and cardboard spools can suck…
And having then re-wound onto a proper spool over night while the filament is dried and goes on soft enough to stay nicely wound up…
Tempting indeed…

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