More from Takuan Soho in Unfettered Mind:
There is a saying, “Sever the edge between before and after.” Not ridding the mind of previous moments, allowing traces of the present mind to remain – both are bad. This means one should cut right through the interval between previous and present. Its significance is in cutting off the edge between before and after, between now and then. It means not detaining the mind.
Thank you for practicing,
Genju
108zenbooks 
Very cool – “not detaining the mind.” Thank you!
I also liked the expression ‘ do not let your thoughts to steep like tea’
Cutting edge is more like the chopping of vegetables for salad.
The detatining of the mind..what about contemplation? Are we not resting the mind on something?