I think this link will answer your questions
Karen Copeland, Ph.D. Boulder Statistics, Boulder, CO 80304https://community.jmp.com › kvoqx44227 › ...
Dr. Copeland says, "
In the case of just two treatments the student’s t-test is often the appropriate method to test for a treatment effect. However, using multiple applications of the t-test to test multiple comparisons within a single study is not appropriate. Rather, one should choose a multiple comparison method suited for the particular question your data is to address."
JMP Systems Engineer, Health and Life Sciences (Pharma)