Um. forgive me if I am wrong, but the dinner parties I have gone to and the dinner parties I have given don’t work like the above.
When I am hosting one–I ask ahead of time for allergies. “Allergies” can and is used as a euphemism for dislikes or true allergies. I take note and plan accordingly. I have never had anyone admit to more than one or at most 2 allergies to food. More often, it is wine that is incompatible with certain meds etc. If I am dying to try this new X–and I know that a guest is averse to it–either I don’t make X or I dont’ invite that guest this time around.
When I am a guest, I express my thanks at being invited, and ask if there is anything I can do/bring. If not–yay! I bring a bottle as a host gift.
Now, at every, every dinner party I have been at–there is a selection of food. Usually, since I don’t know too many vegetarians, there is a meat dish, a starch of some kind, a salad and/or veggie, wine and dessert–fruit and cheese or something sweet.
I, as a guest, have no burden to taste/eat/finish any of the above. If I don’t care for the starch, then I pile on more veggies. If it’s the meat, I take seconds of the starch–whatever. I may well place some of the food in question on my plate, but it will not be consumed.
The point is that I also compliment said host on the effort and the outcome of the meal. Say I don’t like your way with squash. You’ll never hear it from my lips–and it won’t cross my lips either. It is my job, as a guest, to act in a mannerly fashion. It is the job of the host to do likewise–which includes not harassing the guests!
IMO, if you have the time to monitor just what all your guests are eating and how much, you need to develope some Conversation.
NONE of your/my guests are there for the express purpose of sampling your offerings. They are there b/c they were invited for friendship, business or some social reason. If the primary reason for having people over is to receive compliments on your cooking, then please tell your guests ahead of time that supporting the cook emotionally is also on the menu.
That said, would I be disappointed if said guest didn’t try my X? Yes, but if I enjoyed their company and they acted politely about X–I wouldn’t care that much. If I entertained more, I would make a note of the dislike–if I had noticed it in the first place.
For some of you, this is the height of rudeness? I don’t agree with that, but since it is highly unlikely that I will be eating with any of you–so be it.