He seems to have lots of ups and downs offensively. He never impressed me at all on any side of the puck while in CBJ but looking back I was surprised to see him bust out a 40 point and 33 point season 5 and 6 seasons back. Then a bunch of nothing after and before. With a 42 and 36 point season with LA in 11 and 10, respectively.
Not really.
2007-8: 11 in 74, 12 point pace
2008-2009: 11 in 41, 22 point pace
2009-10: 36 in 80, 37 point pace
2010-11: 42 in 82
2011-12: 38 in 82
2012-13: 19 in 44, 35 point pace
2013-14: 33 in 82
2014-15: 40 in 79, 42 point pace
2015-16: 14 in 60, 19 point pace
2016-17: 23 in 82
2017-18: 11 in 77, 12 point pace
2018-19: 13 in 82
He was producing between 33-42 points or pace for 6 seasons. PP points played a part and ES had more fluctuation but it's a pretty consistent run with 8/6 seasons being around 20 ES points. 2010-11 stands out for a low ES season and 2016-17 stands out as his one good ES season in the last 4 seasons. He's 2 years removed from said season.
ES
2008-2009: 5, 10 point pace
2009-10: 23
2010-11: 13
2011-12: 21
2012-13: 11, 21 point pace
2013-14: 19
2014-15: 19
2015-16: 8, 11 point pace
2016-17: 20
2017-18: 11, 12 point pace
2018-19: 9
Michalek was even worse in year 2 than he was in year 1 and Michalek is the more comparable guy to JJ, so I wouldn't be holding my breath on that
It's been awhile but iirc year 2 was Martin's bad year. Meh in year 1, bad in year 2 and then what he was supposed to be. And, "that defenseman bounced back in year 2" sounds a lot like "Gonchar fixes defensemen so it's fine." Players need to have the abilities to bounce back or get fixed, it's never been turning a dumpster into a Ferrari.
I'm really not sure why anyone would be counting on JJ improving. If anything it's likely he's worse because he's another year older and Sullivan has already tried pretty much everything to get something out of him. The guy is an ageing low IQ player who was never all that and it's not like last season was his first bad one. The physical gifts started fading and this is what you get. Losing weight and having a damn year of the system under his belt isn't going to fix him not being able to handle the puck or buy him enough time to make a less terrible decision with the tools he has.