What is the blonding point when using naked portafilter?

Yes, I did search and read through prior threads (see below).

So are my "best answers" correct?
My best answers are :
* exact blonding point is still debatable
* most will agree it is when the flow cones starts to widen (instead of tight flowing cone, the cone started to expand out ; expansion side on the flow cone is side closest to the plane of the portafilter basket)?
* and another clue is to look on surface of the espresso drink for pale color
Why should I care about blonding?
but w.r.t. taste I find doing this will usually result in shot being pulled too long vs. when I use the cone change

This video has bottomless portafilter.
When did this espresso extraction go blond? [video quiz]

This video has spouted portafilter.
When did this espresso extraction go blond? [slow motion video]


Background:
* My questions is only for when using naked portafilters. I only use naked portafilters as I enjoy seeing the espresso flow. Also since I only make at most three espressos per day, I like the unforgiving nature of naked PF (e.g. slight channeling will not be detected by my novice taste buds but great not to see channeling and great to see the barbershop sign color pattern flow and centered flow cone etc.)
I hate my naked portafilter
* Yes I know, blonding point is not the sole determinant of stopping the extraction. It is but one variable; taste being the ultimate determining variable when to stop extraction.
Monitoring extraction tail/flow rate

Hi, I am not clear on what is the specific question? Regardless, I appreciate the post as it collates some really good threads on the topic. It was interesting to read the varying opinions though I'm no closer to understanding blonding and its relationship to extraction than the last time I read up on the topic. To me the color of the flow just seems like a continuum, in which blonding is not a defined point. To me it just seems like for a given coffee the extraction color is just one more parameter you can correlate with other parameters in relationship to the taste of the final product. But I am still on the very early/steepest part of the learning curve compared to most other folks here.

iploya, sorry I was not clear with my original post. I have edited it and hopefully the question is clear.

To me because the change is color is at times very subtle and depends of lighting conditions, I was wondering if the flow cone changes I mentioned is another indicator AND if so an earlier indicator.

BTW, my preferred stopping point is
(A) find taste & balance & body I like (after first determining brew ratio of course)
(B) note that brew ratio
(C) repeat that favored brew ratio or vary it

So why am I asking about blonding point? So that I have another variable I can use when brewing espresso.

mdmvrockford wrote:What is the blinding point when using naked portafilter?
...
* My questions is only for when using naked portafilters. I only use naked portafilters as I enjoy seeing the espresso flow. Also since I only make at most three espressos per day, I like the unforgiving nature of naked PF (e.g. slight channeling will not be detected by my novice taste buds...

You've done some good research, but you're making a flawed assumption, and thus asking the wrong questions.

Why would you think the absence of spouts would change how the shot develops? There is NO difference at all. It's just VISIBLE with a bottomless portafilter.

Jack