Four prime is more than you think but five prime is even more. Here jumping over the prime costs you 10% more gammons (10% to 20%). But as a reward you will get 10% more single game wins (30% to 40%). At normal match scores and unlimited games this is a very good deal because down to 5% increase in single game wins is acceptable.
As a result, it is a good habit to trust five primes. When it is the opponent’s turn s/he will remain behind the prime 25 times out of 36.
