Let's tell it like it is wrote:
No...we can't say for sure about 2015, though a "double time loser" as you say, suggests career doper to me. But as I pointed out earlier, his silver medal at last year's WC with one of his faster times (9.89) at *37* yrs old is laughable!
Here's a good presentation on Gatlin; his cycles, why he used T, and how he got caught:
+1
As for the human limit, who knows. But now with Coleman provisionally banned, we cannot avoid acknowledging the fact that literally everyone who ran 9.80 or faster either got once banned or DQ'd (Bolt) because of an anti-doping rule violation or later shown to have been doping (Greene).
Counting DQ'd Montgomery, that is a full 100% of the 10 fastest ever!
Top-10
Bolt (doped trainer partner, Jamaican clen scandal, DQ’d in 4x 100 relay in Beijing)
Blake - doped
Gay - doped
Powell - doped
Gatlin - doped
Coleman - prov. banned
Carter - doped
Montgomery - doped
Greene - doped
Mullings - doped
Thompson – 9.82 with a 1.7 tail wind
Thus, Thompson's 9.82 with a 1.7 tail wind is the fastest untainted performance.