allThumbs

Very true. I don't disagree.

At a distance, though, reality can take on funny appearances.

You are correct, sir. Updated accordingly.

EDIT: Wow, this is downvoted? Really?

I feel like things are operating according to the following pattern:

  1. Go to college:

     a. spend many semesters in lectures
        all of which tangentially brush 
        upon the final exam based on the 
        whims of the lecturer.

     b. cram for final exam last minute 
        panic to crunch memory according 
        to advice on content which was 
        brushed upon during lectures.

  2. Interview for job:

     a. cram for interview by going to 
        coursera to crunch memory according 
        to interview memes based on the 
        whims of the interviewer.

     b. spend the rest of term of employment
        exercising skills which tend to be
        tangentially brushed upon during
        both interview and schooling while 
        the majority of actual tasks are often 
        googled and stack-overflowed
        into place based on arbitrary design 
        decisions and politicized stack
        choices.

  3. Results:

     a. good interviewees have learned 
        appropriate memes to reassure interviewers.

     b. good students have learned obligatory cruft
        to reassure professors.

     c. actual necessities are tangential to
        many or most entry barriers.

How accurate is this?

They'd need your whole hand, since any finger can be used for a smartphone biometric scanner.

Truthfully, lots of different scannable areas will unlock a phone. I've successfully and reliably configured my toes, the knuckles on my hands, and the tip of my nose. All of them work pretty good.

Unless observed using biometric security in a specific manner, an adversary might have a hard time deducing what kind of print will provide access.

Even if they've determined that the phone contains biometric scans tied to security, how would they know it's yours, and not someone else's, or even a specially printed 3D key ring fob or something?

Then again, criminals don't always think deeply about such details during a crime. They might just chop off both hands, grab the phone, and figure out the rest on the run.