Fuel injection engineers and s/w guys need a specific set of terms that match up with the functions (sub-routines) that they code. So some of the terms are not in common usage.
Tip in and tip out are 2 such terms.
They refer to
increasing the throttle angle (tip in)
and decreasing the throttle angle (tip out)
makes the butterfly more open (tip in)
and makes the butterfly less open (tip out)
We will go into more of the inner functioning of our EFI systems in due course. So forgive us for not answering your question straight away.
The answer is involved and in order to answer it fully we need to setup some baseline terms and functionality first.
And we'd rather do it correctly once rather than piecemeal a bunch of times.
An illustrious quote from vermin:
"I lie to myself because I am the only one who continues to believe me."