xkcd #2942: Fluid Speech
Alt text:
Thank you to linguist Gretchen McCulloch for teaching me about phonetic assimilation, and for teaching me that if you stand around in public reading texts from a linguist and murmuring example phrases to yourself, people will eventually ask if you're okay.
Turning 'potato' into 'puhtaytuh' is an example of what they're talking about. Saying 'puhtaytuh' involves less mouth movement than saying 'potato'.
Try using 'hot potato' in a sentence and you'll probably notice that the glottal stop at the end of 'hot' gets toned down or dropped. The 't' sound will still be there, but your tounge wont move as much as if you say 'hot' on it's own.