The basic time is very important, because the wind changes a lot of the final times.
The stupid people talks only about time without wind because they dont know about sprint
The best basic time for Lemaitre is 10.06 -1.2 in SF Barcelona Euro, 9.99 basic time in 2010.
In 2011 his best basic time was 10.00( 9.95 +1.0 Stockholm)
In 2012 was 10.03 basic time , 10.04 -0.1 Rome
And in 2013 was 10.02 basic time, 10.00 +0.4 in SF Moscow
I would not tell regression, but it is very sure that Lemaitre in the last 4 years is not progressing in his times.
Lemaitre runs usually in 10 low without wind when he is in good shape and sub10 with average wind.
His 9.92 was with super strong wind, +2.0 , max legal wind.
Looking his very bad first 30m yet, I dont see him big improvement in his 9.92
Perhaps he can improve his 9.99 basic time but without strong wind he will never break his record.
Regards