Botha Pushes Easing of Apartheid But Doubts Remain Among Blacks
South African Govt recently announced several plans to change fundamental aspects of apartheid; Botha Govt has accepted recommendations that will give many blacks trade-union rights and scrap some elements or pass system that keeps hundreds of thousands of blacks on run from police in 'white' areas; Govt has commissioned reviews of size and shape of fragmented tribal homelands assigned to blacks and rights that 9 million blacks living outside those self-governing tribal reserves have in areas allocated to whites; Prime Min Botha has asked Parliament committee to look at question of extending political rights to blacks outside tribal areas; Pieter G Koornhof, new minister for black affairs, has shown flexibility toward blacks that has startled those used to high-handed attitudes of most of his predecessors; official statements on plans for union rights and pass systems, however, are worded in general terms, leaving important points to be resolved; it is already clear that elements objectionable to many blacks are to be retained, at least in initial phase; Koornhoff por; illus (L)