Doctrinal?
It's insulting to God (and unloving to the brethren) to say that the death of God's Son on the cross wasn't quite good enough.
All sin was forgiven, the need for any penance whatsover removed, and the need for some so-called final cleansing like "Pergatory" destroyed when Jesus died on that cross. When God looks at those who have accepted His Son's death on the cross, He sees NO sin at all.
What do some Catholics say when someone asks about going to heaven -- well maybe, well if you have no "mortal" sins unconfessed, well if your loved ones pray you out of Pergatory, well if you done enough works, well, well well.

That's good news?
The Bible says accept what Jesus did on the cross and confess Him as Lord and Savior + NOTHING

and salvation is yours!!!

It's a GIFT -- bought and completely paid for by Jesus
God is NOT concerned about sin anymore regarding our right-standing with Him. Jesus died for ALL sin, and all who accept what Jesus did are put in right-standing with God. Amen.