Yes, takes a leap of faith and the flexibility will seem unnerving to anyone accustomed to calendar based plans. Not only can the calendar be completely blank, you always have a choice of alternates on any particular day, plus the option to vary the time you can train today, plus an option to free ride outdoors. Yikes!
However, there is an aha moment along the way when you realize “whoa, this is so much better than following a filled-in calendar plan”. Your XPMC chart will reinforce that belief.
I assume you’ve seen my 120 day indoor experiment thread –
Pre-Base to TED; 120+ days; 100% recommended workouts completed at 100% difficulty - General - Xert Community Forum (xertonline.com)
Another shock for those weaned on SSB training is how much easier Xert’s Base will feel although some workouts share similar characteristics. Xert’s strain model is different though and their progression is a hybrid polarized approach that changes focus and intensity as you move through the phases.
I encourage newbies (esp. trial users) to experiment rather than stick with any one set of parameters. For example, use Filter to see what would be recommended if you change duration and athlete type (Focus) or difficulty (diamond count). Play with the Freshness Feedback slider 10 pts at a time and watch changes in either direction (recommendations and form prediction on the Planner). Change ATP type and ramp rate (IR) and watch what happens with the ATP slider
You can always change things back to what you plan to use for the time being. 
NB Now I know whose wheel to jump on before the county line sprint.