There is a happy medium between slow and hard and fast and floppy - that's the point at which best germination and growth occurs at a steady rate. It isn't just dependent upon the soil temperature, but what you do when the seedlings are up.

There is an obsession with getting things to germinate as fast as possible but there's no point if the light or air temperature are completely unsuitable.

Equally, you have to realise that minimum temperatures will mean many of your seeds just won't make it.