At https://www.blackjackincolor.com/penetration1.htm, Norm demonstrates why the depth of penetration is important in card counting of blackjack. The deeper the penetration in the shoe, the larger the range of HiLo true count.

When the penetration is one deck or 52 cards, Norm shows in a chart there that the true count range is -7~+8. This does not make sense to me. Suppose 52 ten-valued cards are dealt out from a six-deck shoe, then the true count will become -52/5=-10.4, which is out of the above range. Do I miss something here?