Consonant/Consonant Linking (Assimilation)
It goes without saying that most native speakers of English link two words together in fast speech.
Here are patterns that I'm aware of,
T+Y = CH as in "Don't you"
D+Y = J as in "Did you"
S+Y = SH as in "Bless you"
Z+Y = ZH as in "How's your day?"
However, yesterday I came across the unfamiliar cases of consonant linking as below,
1./ t / changes to / p / before / m / / b / or / p /
as in "that man", "set back" and "last post"
2./ d / changes to / b / before / m / / b / or / p /
as in "good morning", "blood bank" and "bad pain"
3./ n / changes to / m / before / m / / b / or / p /
as in "one me", "open book" and "pen pal"
4./ t / changes to / k / before / k / or /g/
as in "credit card" and "cut glass"
Here is the Youtube video from BBC English that explained how people pronounced "credit card"
5./ d / changes to / g / before / k / or / g /
as in "cold call" and bad girl"
My question to native speakers of English
Do you really speak like that or it's common only in British English?
Thank you very much in advance. Your answer will be highly appreciated.