Jackpoteers (& clones) double-feature exchange glitch

[CT229]

As you probably all know, once on the feature in Jackpoteers/Lotta Luck/Fort Boyard, you can restart the feature by nudging in 3 numbers in a row (you have to have the exact number of nudges and NOT fill the fruit matrix) or by taking the same from Golden Hold.  Back in the day when playing these in the wild, I found that sometimes you could "mash the buttons" while it was restarting the feature, and it would restart it again instantly, in a slightly odd state - you would have no nudges/blasts, you would be on the same ring/level as before, but perhaps most interestingly the red trail would hold over (but the bulbs wouldn't be lit).

Anyway, messing around with the emulator I've narrowed down exactly what you need to press, and when - basically, you just need to start the feature by gambling a win and exchanging, NOT off the trail.  This will make the glitch 'active'.  Then, take either nudges or Golden Hold and get 3-in-a-row, and once the feature is restarting, simply hold your finger on the exchange button, and it will restart a second time.  (You can then do the same thing again again on the subsequent feature that starts.)

The time when it is most advantageous is when you have a red number displaying, and the red trail is on 8 - the restart will then hold the trail over at 8, and it will apply the red number showing on the reel, making the board invincible.  Obviously if you're buzzing it up and knocking back reds it's neither here nor there really, but there were definitely times when this was useful as there are plenty of boards when it will happily go to 8 on the red trail but have no intention of actually going invincible, and you can push it over the edge.  So maybe good for a quick jackpot steal, or, I even found occasionally, when playing for afters - sometimes it was worth restarting the feature on the 2nd ring just so you'd get a couple more guaranteed spins (and maybe land a Locomotion or something).

I've often wondered though if I wasn't missing something else more useful you could have done with this?

(I did make a video but the quality is pretty crap: https://youtu.be/OQKRb8L7lpg?t=279 )