Like Desr said if you leave it in the jar then it won't fruit. The glass will prevent the mushrooms from forming because they won't be able to break through the glass. That is why you remove the cake when the mycelium
is fully formed.
The shroomery explains what dunk and roll is all about.
http://www.shroomery.org/5188/What-is-Dunk-and-Roll
There is also a good explanation of why advanced growers do casing despite the difficulties that can arise.
http://www.shroomery.org/33/The-Importance-of-a-Great-Casing-Yebo
Don't worry about casing until you have the basics down. Once you are confident with dunked cakes you can worry about the more advanced stuff.
edit: I did not know about the Chronik Tek.