Maintaining speed in winter

Should we come away from the track and speed training on the flat during winter for any time atall?

I am thinking it would be more advantageous to leave in just 1 short speed session per week on the track eg. 2 x 30m 2 x 50m than to drop speed completely. Hills can give us a break and maintain acceleration but top speed is always lost.

why not continue to develop speed?

Thats my point. So many come away from speed apart from short acceleration runs on hills.