This is a classic example of where stats become miss-leading.
Oscar's case is probably the easiest to point out. Firstly look at the starting point guard of the team in Paul Henare, who is the second worst starting point guard in the league on the offensive end of the court only behind Rhys Carter. Paul is quite strong, so once he gets someone on his hip he can penetrate quite well, but unfortunately he isn't as great a shooter as Brett Maher and tends not to create a driving lane off the dribble as often. Conversely Oscar would find this year that opposition defences can afford to not collapse to cut off the driving lanes when it comes to the point position (the D collapses when Powell drives but Powell is a NBA hopeful ball hog from which once the ball is passed to it is never seen again), hence the defender can stay at home on Oscar more often. The best way to stop a spot-up shooter is to stop him from catching the rock. Keeping this in mind it's not surprising to note that despite Oscar's increased playing time his 3point shot attempts per game have only increased from 5.1 per game to 5.7 per game.
So when Oscar moved from Adelaide to New Zealand it was a move whereby he would have to expand his game a bit to keep his stats on the same level. While progress has no doubt been slow there have been some signs of improvement. He has been more willing to put the ball on the floor and pull up off the dribble for the jump-shot. His on-ball defence has improved as the season has gone on (something which wasn't a focus at all in Adelaide) and he is no longer getting beaten by a simple head-fake now. Also his rotation has somewhat improved (he still does those soft 3 point play fouls sometimes and sometimes he get embarrassed for it, like the Abney dunk).
As for Jacob I haven't seen him play as much, but when I have, the first thing I notice is he doesn't get to back down defenders in the mid-block like he used to and get his turn-around shots. He used to be able to in Adelaide catch the ball and back-down for a good 3 or 4 seconds with 4 other 3 point threats on the court and not expect a double, but the Dragons don't have any set for him like this within their offence. In fact the Dragons offence is incredibly perimeter orientated and doesn't play to Jacob's strength. Meanwhile it's only Heal's first season as coach, and I don't see many people proclaiming his greatness as a coach yet.
In the end however, what really matters is the attention to young player's games that Smyth devotes, and the ability to use that to recruit young talent which is the major concern for the club moving forward. Unfortunately for Phil, he seems to spend more time attempting to chase away young talent than actually trying to recruit it.