Why is PCT front loaded?

For years I've always seen any pct follow the common max dose, and then weekly taper. A common Clomid pct is 100/50/50/25.

WHY is pct front loaded and then tapered? Within a couple of days you're at max level(far higher than you'll be in subsequent weeks), so it's not to reach an effective dose.

I started researching pct for men under a doctor's care(so legit TRT), and it seems most doctors prescribe serms at the same dose for between 4 to 8 weeks. There is no front load, and no taper either. I've tried looking for actual medical research on this, and I couldn't find anything.

Does this basically boil down to steroid lore? Or is there an actual reason for running higher doses and tapering off? I've never seen it adequately explained for why this is ideal. The closest I've seen was someone off-handedly saying you need more to "kickstart" things.

I'm aware that many TRT doctors are not especially informed about steroids or serms(though that cuts both ways as I've seen some remarkably stupid things said on steroid boards). So I'm not saying this is a case of TRT docs being correct and experienced steroid users being incorrect. But I am curious what is the difference in how a PCT goes if you used a high dose with taper, versus a lower dose the entire time.

So I'm asking two questions.
Why is it high at first. What benefit does this provide over running a constant lower dose.
If you compared two PCT runs of Clomid 100/50/50/25 to 25/25/25/25 how would the 2nd differ from the first at the end of week 4?

To get therapeutic levels built up instantly.