I've recently come to believe the differences in hypertrophy are negligible between eccentric and concentric focused movements, but can't find any recent, compelling research that says so. There was a 2017 meta analysis by Brad Schoenfeld (basically THE hypertrophy researcher) that showed a pretty significant different in hypertrophy: an average of 10% vs 6.8%.
I know Greg Nuckols from StrongerByScience believes this is mostly caused by lifters, especially untrained lifters which most of the research is on, having spent less time in eccentric phases so there is more opportunity for growth there, but it will eventually plateau.
I know Greg Nuckols from StrongerByScience believes this is mostly caused by lifters, especially untrained lifters which most of the research is on, having spent less time in eccentric phases so there is more opportunity for growth there, but it will eventually plateau.