Tom Doak may remember all this better than I do, but I recall someone saying the waste bunkers didn't work because "grasses grew too good! (and weeds). And, I think Pete used about 7 different grass varieties, including some on the mounds for color difference, but my bet is that good old Bermuda takes that kind of spectator traffic the best, hands down, and thus it was all converted.
I may be mis recallling some of those details, but it's not unusual to find that superintendents need to change out certain things to make them more practical to their use.