Exactely the reason why debuffs were picked up to get more relevant data
As I said before it all started with people parsing damage and noticing quit a big difference in nukes compared to when we had the dunna GEO doing Languor.
It followed again when in another group, this time in Reisenjima, a similar situation happened and you could see that by the difference in the average timer to bring down a certain NM we were farming.
All that raw data though is a bit more complex to discriminate and a bit too generic.
After finding out that a lot of people, just like me, were surprised by the fact that appearently we couldn't compare 1:1 the data SE gave us for Threnodies and for the Meva debuffs (Languor, Frazzle) that's why I decided to do a small test on enfeebles, for the purpose of that test partial resist on durations didn't matter, just land/fullrest is what mattered, making the test much more valuable even with a small sample.
I don't really remember right now which mob we picked for the test but I seem to recall it was a Ru'aun T2? Target was picked because of no known relevant/resist trait or elemental affinity.
We tested I think at least 2 debuffs (maybe 3? Think it was 2). For all of them we did around 30ish casts with nothing, then 30ish casts with the relevant T2 Threnody and 30ish casts with Languor.
I don't thin we've ever seen resists with Languor, should check the original report, maybe one or twice. Resist rate with nothing was pretty high, and resist rate with Threnody was definitely better but I still couldn't land like >50% of the time, despite immunobreaks.
I don't think that test alone is enough to demonstrate anything, but when you see it as an addition to many other similar reports/tests by other people, it kinda starts to matter despite its low relevance alone, if you get what I mean.