Pharmacokinetics (half-life and other variables) of drugs and their different delivery methods are public knowledge, there are individual differences in metabolism of course.
When it comes to designing drugs there are quite a few things that are done in the delivery mechanism of the drug that can effect half-life.
For most drugs the elimination half-life is so long that a faster route of administration makes minor difference. For caffeine for example it's about 4.5 hours. You can shorten the absorption from < 1 hour to seconds but that probably won't matter much in this case.
You can make the absorption slower in a way that makes a difference however, for example there are several timed release versions of methylphenidate.
Pharmacokinetics (half-life and other variables) of drugs and their different delivery methods are public knowledge, there are individual differences in metabolism of course.
There are number that are public knowledge. Those numbers do have meaning. On the other hand individual differences are also important.
A lot of pseudoscience comes from people having a rough theory about isolated facts and personal observations. I think it's often very valuable to stay with personal observations instead of trying to fit them into a simple theory you made up that se...
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.