Truth be told
The gemara says that rabban gamliel did not let talmidim who were not tocho kboro in the bais medrash and reb elazar ben azaria did let them in. this esulted in more torah learning.
tocho kboro translated means inside like outside.
With my gemara learning training to back me up i suggest that the amoraim did not argue as to the evil of not being tocho kboro, but rather they argued as too whetger such a person should be allowed in the bais medrash.
On a previous point i was thinking about chitzonios meorer es hapnimios and i think that this itself is what causes that which i said in my original (civil) post meaning the following: When a person acts like they enjoy doing something that will affect their perception of themselves and they will enjoy it. (mesilas yesharim) When a person acts like a tzaddik they will end up thinking they are a tzaddik which will not change what they actually are for the better. (Me)