The difference between the LA Times poll and all the others methodologically is that the others count only whole votes for candidates and some will add in leaners while the LAT poll allows respondents to rate their commitment on a 0-100 scale. Other polls that measure commitment separately if at all consistently show Trump voters are more committed. It has an argument if news at the last minute moves weak votes which it is trying to anticipate because it always seems to happen as surprises. Could be way off if there were no surprises after the last polls. But if that proves more accurate this time, everyone will be doing it that way in 2020.
Thanks for the clear explanation. Their results make more sense to me now.
If the poll website is accurate and honest, your claim does not apply to the poll that is the subject of the OP.
Every day, we invite one-seventh of the members of the UAS election panel to answer three predictive questions: What is the percent chance that ... (1) you will vote in the presidential election? (2) you will vote for Clinton, Trump, or someone else? and (3) Clinton, Trump or someone else will win? As their answers come in, we update the charts daily (just after midnight) with an average of all of the prior week's responses. To find out more about what lies behind the vote, each week we also ask respondents one or two extra questions about their preferences and values.
You'll find that neat the bottom of the page, under "About the Survey"