People were punished for "win trading" at the end of last season, which this would likely fall under with Twisted Treeline's small queue. We've also seen a few more Intentional Feeding bans popping up in Player Behavior lately, which is an indicator Riot is messing with that system.
It's a gamble. If you're going to try to hit Iron, rather than intentionally feed it'd be better to impose a handicap on yourself and play as normal. Such handicaps could be covering your minimap so you can't look at it, or only farming with Auto Basic Attacks on instead of trying to last hit, or zooming the camera in.