I agree with you 100%- you here similar claims by cricketers over 20m. When you add reaction time, adjust times for the fact most athletes have momentum before the first gate is broken, very few footballers or cricketers would break 3.00 for 20m or 4.00 for 30m. When you look at SR required to break 4.00 for 30m – it equates close to 5 strides per second @ 30m and I haven’t seen any footballers even come close to this SR.