Speed endurance the key to *all* 11/12second sprinters?

The Q & A with Stephen Francis indicated that general fitness plays a significant part of the training programme for Powell with 1,000m time trials, burpees and other calisthenic exercises going on until December (going on seemingly beyond the period elite athletes would ‘normally’ do GPP). He even indicated that it was a single periodized l-to-s programme (possibly to accomodate a lengthier than normal for elite athletes, GPP). Allan Wells had two 6 week conditioning blocks consisting of calisthenics, speed ball and plyos before he ventured (back) onto the track. Does this indicate that there are greater advantages to having the more extended GPP for elite athletes in terms of the general strengthening of the organism than has previously generally been recognised, and without a negative impact to overall performance due to the slightly shorter SPP.