when native speakers pronounce the phrase "Have a good time" do they tend to drop the "d" in the word "good"? The "t" and "d" are in the same tongue position and the only difference between them is that one is voiced and the other is unvoiced. I'm wondering, do Americans tend to drop the "d" in this situation in connected casual speech? or they link the two words together holding the airflow on the "d" and releasing it on the "t".
I'm British. I would say that very few speakers of English make two separate tongue 'clicks'. I have heard a few people that do - I'm pretty sure there's a British politician that does it. I'll try to remember who.
Experimenting for myself, I can say that I make the tongue movement only once, however I can easily distinguish between "goodtime" "goodime" and "gootime"
I may return to this answer to give a detailed analysis of the three. I won't do so until you hear from an American English speaker which is what you requested.
You may be interested in the following interview, Five Minutes with: Brian Sewell . The speaker is an art critic. He is well known to be someone who prides himself in his precise pronunciation of English. Some would criticise him as sounding too 'posh.'
If you listen to the interview from about 02:16, you will hear him say "I need to go to a museum. I need to be fed ..."
Native US English speaker here: A standard US accent would link the two words together holding the airflow on the "d" and releasing it on the "t". Essentially, it become a hybrid sound that starts softly and ends sharply, by increasing the pressure of the tongue against the roof of the mouth. The position of the tongue does not change, just the pressure. It is the same in British English, except the "t" ending would be sharper and more crisp.