When Ovie-Backstrom-Oshie lose the puck - or lose the face-off in the D-zone - they can't get the puck back. There's not enough quickness and puck retrieval capacity among those 3 to get it back.
Todd broke up Kuzy and Ovie and the result was both went into no-show mode on 2 different lines. Also not sure why there's the ongoing angst about who should play with Ovie and Kuzy until 43 gets back - it seems pretty clear to me that Conno had the best chemistry with them.
It's Oshie.
8-92-77 in
2015-16: 55.7 CF%, 10 GF, 5 GA, 60% SCF, 68% HDCF in 178 minutes together
2016-17: 57.7 CF%, 5 GF, 0 GA, 61% SCF, 60% HDCF in 79 minutes together
2017-18: 61.9 CF%, 5 GF, 2 GA, 71% SCF, 62% HDCF in 30 minutes together
They outscored opponents 20-7 at 5 on 5 in their time together during the last three years.
You're right about 8-19-77 and their lack of foot speed being a problem on puck retrievals, it's a big reason why I dislike that line.
It's why they're one and done as well in the offensive zone.