A few questions about Jeff Galloways 5k plan?

I have started to use Jeff's plan after successfully running 5k under Greg McMillan's plan. I chose Jeff's plan this time as his seemed better suited to improving speed, which is what I want this time, as I am planning to run 5k with a timed goal of 25 minutes. I do have a few of questions. 

First, I am used to routine, but Jeff's plan comes across (at least thus far in week 1) as maybe too adaptive. It seems like, for example, in the run walk run, I have full discretion to choose how long I do of each. Is there any opportunity to set intervals via the plan i.e run for 4 minutes and recovery walk for 30 seconds?

Secondly, will the training plan eventually become more routine and rigid? As opposed to 'go for a run and slow down when you feel like it', does the training plan eventually take an approach of 'Run for 'X' amount of time at 'X' pace then walk for 'X' amount of time'? 

Third and last. Does the training plan eventually introduce longer runs? I feel endurance/long distance running (without stopping) benefited me in a sense that it conditioned me to run longer distance i.e a 5k.

Thanks in advance to any help and info given.