Here's a fun set of graph. Plagiarized from "Diabetes Mellitus: A Fundamental and Clinical Text 3rd Edition".
BTW, in case you guys haven't figured it out, I love graphs.
It shows different regimes that have been popular or at least used over the years.
First three graphs are not really basal+bolus centered:
R+N once a day. Note that the very large NPH dose lasts a long time.
R+N twice a day. Note that the smaller NPH dose lasts a shorter time.
Lente + a fast acting analog insulin with each meal. Note that Lente definitely does not stretch the way NPH does. I haven't seen Lente or Ultralente in a long time. This IMHO is not basal+bolus, the Lente just doesn't work like a basal.
Fourth graph actually begins to have the basal+bolus concept. NPH twice a day plus fast acting with each meal. IMHO this is just sort of the bare minimum in basal+bolus.
Fifth graph is NPH 4 times a day with a fast acting 3 times a day. This is similar to what I did for a couple of decades (where "fast acting" was regular). Works pretty good IMHO, because each individual NPH dose is small and the additive curves of all 4 NPH shots is really quite flat in a highly consistent way.
I think graphs 6 is fast acting in a pump. A 7 shows more modern (say post-2000) MDI routines with analogue insulins for both basal and bolus. Note the inaccurate mythology that lantus or levemir is perfectly flat. Not true!!!!!!
Graph 8 shows what I've heard some folks here talk about, 3 different insulins, with a NPH as a "kicker" in the evening maybe to help work against dawn phenomenon over night.