Stokes Seeds does a fantastic job with giving optimal soil temperatures for germination of specific plants. They are in ATP Recommendations. The germination temps are not ambient temperatures, it is soil temperature
For the most part, stratification cracks the seed coat for the water to penetrate. Once the temperature of the soil is compatible with the liking of the particular seed, it will sprout. The tough seed coat is there for protection to not germinate before the environment is ok
