ok....but you very well may be seeing correlations that don't exist
* Harkless was 22 entering his 4th season when he joined Portland. In his previous 3 season he attempted about 300 three's. In 3 seasons in Portland, he attempted over 500 three's, nearly doubling his volume over his first 3 seasons. That increase in percentage you noted could as easily been due to the natural progression of a young player while increasing a shot type
* Aminu was 25 entering his 6th season. But in his previous 5 seasons, he only attempted about 250 three's; then, in 4 years in Portland he attempted over 1300 three's. So, he went from averaging 50 attempts a year to 330. That could be the reason for improvement rather than the Blazer system or Dame/CJ
for Gordon, he wouldn't be young like Harkless, so there likely wouldn't be an upside shooting bump from that. And, he's been a volume three point shooter; he's shot over 1400 three's in his career and has averaged 300 attempts over the last 4 seasons. So he wouldn't have the increased volume factor working that very well may have been working for Aminu
Melo did shoot better than he has for several seasons, but I'd imagine if you backtracked thru the veteran additions like Steve Blake, Mo Williams, Arron Afflalo, Dorell Wright, Gerald Henderson, Nik Stauskas, Anthony Tolliver, Kent Bazemore you'd find a pretty mixed bag of correlations
don't misunderstand....I'm not saying that Gordon would not be a good addition. I'd be reluctant to see Portland pay a substantial price for him because he just doesn't impress me as the type of player that will alter the team's trajectory