Blackjack Strategy When Splitting a Pair of Fours
Split: When the dealer has a 5 or 6 showing.
Hit: When the dealer has anything else showing.
Why to split a pair of fours
The whole strategy rides on the hopes that the dealer will bust, it's a very easy strategy. It works by hoping the dealer gets a 15 and 16 because of the numerous tens in play. The dealer then has to hit on anything less than 17. The high chances of the dealer getting another ten or the other cards that will make him go bust are great. It really doesn't matter too much what pair you have when the dealer has a 5 or 6.
Why to hit a pair of fours
If the dealer has anything else showing, a pair of 4's are not very good. If you split these, there is a good chance you would get two fourteens, which are terrible for you. The best strategy is to just hit the 8 and hope for a probable 18 because of all the tens. This is a decent hand in fact.