Grammar books vary vastly in guidance on Modal verbs and the Conditional or Unreal Past. We can exercise our grammar relativity, to manage.
10.4. MORE WORKOUT FOR REAL-TIME TALK

Use of figurative spatial reference for management of grammar.
Grammar books vary vastly in guidance on Modal verbs and the Conditional or Unreal Past. We can exercise our grammar relativity, to manage.
We can use Form Relativity with the Progressive and real verbs. We can use stories. “I’d be reading horoscopes”, says Ms. Seges. “That is …?” (Mr. Seges does not believe Ms. Seges would ever read horoscopes.) “This looks like a calligraphic copy of Vespucci’s letters. It was slipping out of our backyard hedge, no covers or front matter.” “Hadn’t it sure taken a lot to make such a book, I’d suspect that Babbitt next door. Bill once wrote me the book I was looking for was as likely to be obtained as a calligraphic of Vespucci’s originals. It was completely a legend, he checked with the Freeman’s.”
We do not have to view Modal, Conditional, or Unreal Past patterns as separate. With Perfect tenses, our syntactic HAVE helps tell about real time. It has an open real-time frame. With the Unreal Past or Conditional, HAVE tells about hypothetical time. HAVE is not part the real map, then. It comes with an auxiliary compass for relative time.
We can view verb forms as generally relative, for hypotheses. PRESENT forms can tell about the FUTURE. PAST forms can tell about the PRESENT. ANTECEDENT PAST forms can tell about the PAST.
Our use of the word "relativity" is not about physics or families. It is linguistic. We can acquire the Modal relativity step-by-step, and spare our arrows. Let us remember they indicate the target time, not the verb form.
We can actually live only in the real-time PRESENT. Our syntactic HAVE does not bring assertion about real time, when we attach it to a Modal and make a hypothesis. We do not need to view it as open-frame real time, then. We can view it as a syntactic anchor and a closed-frame hypothetical time.
For all tenses, this is always the first element in the verb pattern to change with the time extent (PRESENT, PAST, or FUTURE). It changes the same in our Fields of Time. We can say that it is the form closest to our cognitive ground. It changes the same for our value ON.
Most grammar resources agree that we have four Aspects in English, the Simple, the Progressive (or Continuous), the Perfect, and the Perfect Progressive (or Perfect Continuous). By the label, we can say the Perfect Progressive should have features of the Perfect and the Progressive. We extracted general patterns for the Simple, Progressive, and Perfect in … Continue reading CHAPTER 8. ALCHEMY OF TIME FOR BEGINNERS
The Simple and Progressive Aspects compared: "stative verb" use described with regard to human cognitive activity.
We may find grammar books to tell about “stative” or “static verbs”. The books give lists of such verbs to remember and not to use with the Progressive. Let us think if we could list all words we might associate with love and hate in the alphabetical order, for example? Listing the words would take a long time, and we can speak, write, and read real-time.