Russ, your liver constantly releases stored sugar into your bloodstream. Stored fat also gets converted but slower. There's a lot of biology there, so just accept that there's a constant background supply of glucose that needs to be covered.
One thing your doctors or diabetic educators will not tell you is that each of us has a unique pattern. I call it a basal profile. Us pumpers can put a lot of effort into determining our patterns and matching our basal insulin releases to it. This gives us much better control and much more flexibility to eat or not eat as there are no periods requiring food. This variation is largely due to our liver releasing hormones which make us insulin resistant. Search for Dawn Phenomenon.
The problem with basal insulins is they are smooth and flattish. If you have a humpy profile like me, you have times of the day with not enough insulin and other times with too much. These inefficiencies often lead to hypos, hypers, and weight gain as we add food to compensate. Dual dosages can help, but it's nowhere near as good as pumping. My profile is attached. The yellow is my dose and the blue the effectiveness.
The following image is of different nighttime patterns. It is important to know which pattern you fall into not only to treat effectively but to prevent nasty hypos while sleeping. I fall into pattern D which is the most common and hardest to manage. Search for Symogi Effect.
You may find this document helpful.
BD: Problem Solving and Exercises
My personal opinion is you take Lantus to cover all the lows and suppliment with a short or medium acting to cover all the spikes. The trouble is that would mean me waking up at 5am to bolus.