Reading a Dead Draven

I've got a stream highlight I wanted to share about predicting a kill about 60 seconds in advance on an enemy adc. The key bits that went into making this play possible were

1 - adcs tend to prioritize farming

2 - there is a minion wave heading towards the bottom turret

3 - the enemy sona was mid so we know that the enemy adc will be alone

all of the above lead towards the play seen in the video