I use different Airflo Scout heads on my 11‘ rods and some of the „longer“ Airflo Switch series, also some F.I.S.T., on my 12‘6 and 13‘ rods. It’s equipment I use intensively for fishing TroutSpey and Danube Salmon.
With this I already went down in length for the Skagits. The interesting point for me to use the shorter versions of Skagit Belly‘s was the possibility to adapt them for different scenarios with customized Cheaters and longer, tapered tips: combination of good rod load and more Scandi like presentation, with the option for a customized 3D line for better power transition for casting and depth control.
But I wouldn’t go that far, to use the Scout for the longer rods too.
As the shortest version for a 12‘6/13‘ rod there is the Switch. It’s already a step down and shorter than the average.
And it‘s nice. Adapted with an Intermediate Cheater of 1 m plus 10‘ or 15’ (depending on needs) Rio
tapered exchangeable tips + tippet it’s really nice to cast. Same tuning with the Scout for TroutSpey.
Good anchor, deep load, long distances, 3D line with all benefits. Or downgrading to „classic Skagit“ combination with only 10’ of your T-material or a little longer for all the rest.
The OPST is a different story. It’s completely different tapered.
But the Scout on the longer rods? You would go down two steps in length, to deal with problems and to accept limitations.
Why make it more difficult than necessary and take options away?
I would try to build up the arsenal of rod and line pairings in the logic of best usefullness in the different categories of Skagit, Scandi, LongSpey or whatever. To maximize the adaption possibilities of the different tools, not to be forced to adapt yourself to a limited rod line pairing that is too much out of your average rod-line-length ratio you are used to. If there would be a benefit, of course. But there is none.
There are enough challenges left, to jump and adapt between different rods and lines and all the categories we can choose from for our fun.