Str8shooter48,
I have a blue Encore barrel, that I picked up with a frame I wanted, and the previous owner did what you describe, but reported that it did not make a difference in accuracy. I don't recall if he used the SST you ask about, or remember what combination he told me he tried.
If you are considering doing so to yours, please contact me first about trading barrels. I haven't fired mine yet, but may in February for a HAM javelina hunt, but may use one of the pistol barrels insetad or perhaps a bow.
I have a number of other T/C sidelocks without the QLA and one with the QLA. I like the idea for an Encore barrel as I plan to shoot mine with maxiball or maxihunters that I cast and real blackpowder rather than a substitute. Not that it would be a better combination for that, but because it is what I have a bit of on hand.