I've been gone since 72 or 3 and I still have my accent .... not as pronounced, but it's there.
I've read aloud many times and there are always comments about my accent and I'm never aware of it.
It's just there.
If a native Bostonian speaks in what you call clear English, he or she worked at developing that.
It's natural to say ahnt and unnatural to say ant
To us, it's natural to say cahn't, bahth, Satidy, cah and all the etcetera's we all love.
But hey .... wadoIknow .... I'm jus' a dum retihed truck drivah.
Try with something you have not read prior or know what it is about.