I think the takeaway is that theophylline may help with phase delay. Though, that is merely my thoughts at first glance. Not to mention that this is rat data. Nonetheless, combining this with data on the cAMP and cGMP role in circadian rhythm, I'm relatively confident that methylxanthines have some effect on circadian rhythm. Most likely phase advancing effects.

In practice, this means theobromine should be explored as a treatment for Delayed Sleep Phase syndrome (DSPS). It may also be useful for some non-24 conditions. I may consider upping my theobromine dose so that I can get to sleep early and wake up early.

Also, perhaps I should avoid ethanol in the morning. Hard to say from this data.