I hope I'll be accepted to join this awesome club!
Actually you mean Username.
Okay, added you on. Welcome to the club!
I've added two more awards on the awards list. The Ultimate Supporter Award and Veteran Award. Details for them are in the Awards List on the first post.
Answering the Current Topic:
Special Sweepers make so good use of this move, it beats Flamethrower by a lot. PP is nothing if you make good use of the move. Flamethrower may have better accuracy, but seriously now, having a move that is around 1/3 stronger than Flamethrower that has only 15% less accuracy will be better in my opinion. PLUS it had a TM in ALL of the Generations, unlike Flamethrower, who only started at Generation III.
Fire Blast has got around 1/3 more power than Flamethrower.
Fire Blast has about 1/7 less accuracy than Flamethrower.
Fire Blast has got about 1/3 less PP than Flamethrower (100 divided by 15 is 6.7 Rounded, so 100 is divided by 7).
100 divided by 3 is 33.3, so that is the target Flamethrower needs to beat.
From the 1/7, Flamethrower had 14.287 (Rounded).
From the 1/3, Flamethrower had 14.287 (Method of PP is the reason).
That makes a total of 28.574, which does not meet 33.3.
Which means, Fire Blast is mathematically a few percent better than Flamethrower, at around 4.726%. I searched for the answers through Google. Of course, this is including the PP Method, and therefore there is another way not including this.
But of course, whatever you prefer is your own choice...