Flamethrowers. How to aim effectively?

[my butt is erect]

I'm a 15year+ pretty good player. Yet still it feels very inconsistent how fast I can down someone with flamethrower. Made obvious by the amount of damage ding sounds I'm hearing.

Do you lead the flames much or what? What's the deal? Is it simply wildly inconsistent and weird? Or, is it more like pro spy facestabbers who simply know how to take advantage of a weird system to their benefit?

It seems like the projectile "flamethrower" kills faster even at close range which truly seems to make no sense.

[NightPants(XL)]

yea you lead a bit and fill the area around them also (spas out) so they keep strafing into it.
a real effective means is to bait them to follow you while you strafe backwards and fire and let them walk through a trail of fire. gets em all the time