tec, it's not very good.
I just checked out my 12-man staff. Two relievers have just two pitches (70-80 & 85-71), everybody else has at least a 3rd pitch. Listed below are the 3rd (and 4th) pitch of the other 10 guys.
RP: 40 (but his 1st two pitches are 90-78. Career ERA of 4.63)
RP: 51 (1st two pitches are 81-75. He's a LOOGY)
RP: 59 (1st two pitches are 91-72)
RP: 39-53 (Career ERA of 4.67)
I have two guys with a 3rd pitch of less than 48. One guy has a 1st pitch of 90 vL/vR of 63/78. The other guy has got into 1 game for 1 innings (28 team games) this year. Taylor has a big ugly 4th pitch, too. 48 isn't a very good 3rd pitch. Terrible is probably the right word, especially considering his 4thpitch and he has no special 1st or 2nd.