What is the difference between Aktionsart and Aspect. Anyhow, I'll give it a try. Defined as tense alone, aorist, for instance would be seen as a simple past. Greek tenses depict more than time. This concept is often diagrammed on a time line with action depicted by dots, lines, repeated dots, or a combination of dots and lines.
Aspect takes into account time and type of action as elements in a verb.
It may indeed indicate a punctiliar action in the past time or a linear or repeated action culminated in the past. Perhaps Greek writers employed the aorist to represent action occuring in the present. This has been a matter of great debate in B-Greek. We all, presumably, seek to find out what a writer meant by what he said. Obviously that's not an easy task.