Chickory , volunteer and not

The plan has always been to add the roasted roots to coffee, although most of the time the spring plants are sauted instead. However, there is a host of ideas in the link below new to me, and I wanted to keep the resource.

https://myhomefoodthatsamore.wordpress.com/2010/11/25/cichorium-intybus/

So, a variety of questions arise here:

Have to boil them for 15 minutes?

I found in a book (I'll find it again, someday) about forcing chickory roots for "Belgian Endive." 2 different plants?

More questions than answers.

there seem to be a gazillion types of cichorium. We have a variety that is specifically for eating in salad, it is slightly (but not overly) bitter. Then sometimes we can get the purple tiny-but-bitter kind that is good roasted and blistered.
As for the italian recipe, we often make sauteed arugula or cress. Depending on the season it can be REALLY zingy, and some varieties (like a certain dryland cress I can sometimes get) are downright intense. Still, in Chinese cooking watercress is pretty commonly quick stir fried (as is lettuce) and is significantly toned down compared to raw. No 15 minute boiling, to be sure.