Luck's Labor is broken!?

Gathering is something I do a lot. I joined the Fresh Start server Ennead and have +143.8% Logging Luck, the only way I could increase this number further is to upgrade all my 600gs to 625gs.
I have my own routes and I calculate my yield for everything!!
Now, I got my Music to 150 in order to use Luck’s Labor, which gives a 5% Gathering Luck boost. So why am I getting significantly less wildwood and barbvines? Like A LOT less…
For every 2000 Ironwood I collect I calculated that I earn anywhere from 75-125 wildwood and bardvine EACH!
After Luck’s Labor, for every 2000 Ironwood, I’ve been getting a whopping 30 wildwood and bardvine EACH!!!
How is that possible?! How can adding 5% more luck to my pool decrease my gains by that much? Huh?! Please explain…
This wasn’t just a one off, I’ve tested this several times. The results were the same.
In all this testing, my faction did NOT have the CK fort.