Putting Whetstone in a matchmade activity has had a negative effect on anyone attempting to play the original matchmade deep dive playlist. Its frustrating to have most lobbies be split between players trying to progress through the seasonal activity and triumphs and players attempting to get Wicked Implement. The result has lead to many instances of players quitting a Non-Join in progress activity (which I'm still confused as to why it is one) leading to either party failing either the deep dive or Whetstone.
I Imagine that as more players obtain Wicked Implement the issue will gradually subside, but I hope that we never see a mission implemented in the middle of a matchmade activity like this again.
Whetstone itself is pretty solid, a short but sweet time trial with an exotic reward is always fun to play in my books. Although it doesn't feel like it has the same replay value the other timed exotic missions offer, maybe due to a lack of an extra reward akin to A thousand wings to chase after you've obtained the weapon.
My only pieces of deep dive feedback boil down to wishing that the pressure trials were more understood by players, and I really enjoy the early exploration of roguelike mechanics in destiny 2 and want to see an activity lean harder into them in future.