Re: LAST POSITION !- yes and no
Well... no. I take 3rd base out of habit and because it is easier for me to count that way. After the first two cards are dealt I can count the whole table in about a second so there is no noticeable interruption in my friendly chat with the PC.
It is however NOT the most accurate. The effectiveness of the count is related mostly to two things: 1. The likelihood of blackjacks appearing on the table, this is most significant with ace-counting counts like High-Low or if you use an ace sidecount and... 2. The ratio of high cards in the deck, making it easier for the dealer to break.
Now you place your bet before any cards are dealt. Assume 6 players, there are going to be at least 14 cards dealt before you get to make any play decision and most importantly, before the dealer has to draw any cards. Just peel the top 14 cards off the shoe, shuffle them up any way you want, your odds are not going to change whether you get the first two or the last two, and either are the dealer's. The hell of it is, let's say TC=+5, you put out a huge bet, the hand is dealt, everyone stays, you didn't get a BJ, and by the time the dealer is playing the count is now down to TC=+1 and you wish you didn't have so much money out. Note that none of this has anything to do with your position at the table. Now for your playing decisions, you have to adjust the count on the fly as you see cards if you are going to be playing an index, but being the cards are coming out kind of slowly during the draw it's a bit easier.
Your accuracy will be enhanced by having a lower number of players at the table, because fewer cards will be rolled between when you calculate the count and when the dealer plays. Your hands per hour will also be increased so playing at an unpopulated table is always a good bet for a counter.
When I first started playing I always sat at 3rd base and picked a slow dealer, then I realized that these were both (newbie) counter tells and practiced playing with faster dealers and at all positions. Next to 3rd base, 1st base easiest to count at, but with practice now I can work equally well at any position, and I look for fast dealers to speed up my profits.