There would be no benefit to doing gaslight in an indoor artificial light setup. It's only purpose is to prevent flowering of short day plants in greenhouses in winter when days are too short. Indoors, all that would happen is that growth would be slower because you only get a total of 13 hours light a day.
I'll tell you what does work well though, repeating 6/2 cycle. I find it works better than straight 18/6. Just by visual assessment, no side by side or anything. That's what I use for rooting clones and veg stage. I tried 11/1 too and it didn't work as well. I think I tried 7/1 also and 5/3 was too slow for my liking. All I can say is 6/2 seems to me to be the best of all I tried. All it takes is 3 programs on a digital timer.