The whole "no excuse" doctrine, as far as I can tell from my experience derives from a gross misinterpretation of Rom 1:20. My Pastor used to quote this scripture as "scriptural proof" that no one can claim to "not know", so therefore there's "no excuse" for anyone. I asked him once if he thought Rom 1:20 was a reference to all of mankind, rather than a particular group Paul was referring to. He said he thought it meant all of mankind. So I asked him what he thought about Rom 1:18, particularly the last phrase "..who suppress the truth in unrighteousness." Surely in order to suppress the truth about something, you would have to have some knowledge of what that "truth" is? The rest of the chapter goes on to talk about foolish wisdom, the making and worshipping of idols, and ritualistic sexual abominations. Surely this is talking about people involved in pagan ritualistic worship? He insisted it meant everyone on earth, and insisted that everyone knew, and knows who God is. Yet in 1Thes 4:5, and 2Thes 1:8 Paul makes reference to Gentiles "that know not God". Most reference Bibles say that Romans was written around AD 57, Thessalonians around AD 51. I don't think it's reasonable to suggest that in the space of 6 years Paul had managed to circumnavigate the planet and preach the Gospel to everyone on earth. Christianity didn't reach many countires until centuries later.
Jesus made it quite clear in Luke 12:47-48 that there were and will be those that do not know the will of God.
Slightly off topic, but this really struck me yesterday so I'd like to share it. I was reading Micah and in the last part of verse 2, ch 5 it says "Who's goings forth are from old, from everlasting".....................how can you have an "everlasting" in the past tense? If the past is "everlasting", eternal and infinite, then the 1st sentence of scripture is a lie. In more modern translations it has it ..."from ancient times"....much better.
Obviously yet another attempt by the KJ theologians to insert this "eternity" nonsense into the Bible, because without it, their Hell doctrine falls.