Introduction to OSPF Stub Areas

HI,
I have a question on this point.
Doesnt ABR just generate type3 LSA or type 4 to let us know of ASBR.
Now in TSA, the only allowed LSA’s are 1 & 2. So how does ABR help ?
if an ABR is configured with default originate always, my understanding is that route alwas appears as an O *E2 or Type 5 or External route in the downlink routers . But I am seeing it as O *IA in my setup, R1 – R2(ABR) – R3(TSA) , pls let me know why ?
Addtionally in show ip ospf dbs cmd on TSA router , I see only LSA1 and Sumary Net link States (LSA3) being shown, should not LSA 3 be blocked on this ?
Note:THis is a office setup, working since ages, just chekcing my output there.
Thanks