Should I trust the 'average portion size' syn values for restaurant meals?

Going out for an Indian meal this week for a family birthday celebration. The lowest syn choices that I think I might choose between are the lamb rogan josh or tandoori chicken? I love plain rice so that won't be a problem.
The thing that bothers me is that often you read about people saying that 'average portion sizes' in restaurants are actually larger than the weights given in the food directory syn list.
Should I merrily order my choice in the restaurant thinking that my syns are within limit? I can hardly ask the waiter to weigh my portion can I?
Has anyone ever actually weighed their takeaway portion to check it against the weights listed?
i mat sound a little obsessed but it is only that I don't want to ruin all my hard work over the last three weeks, I've had steady losses so far and want to stay motivated and on track.

the short answer is no, lol, what I do is guesstimate, I look at what I'm eating & try & work out the weight of it then I can work back the syns. I think if you realise it's not an exact amount and don't stress about it you'll be ok.

Thanks, thought so! maybe if I choose something a bit more dry with as little sauce as possible then I won't be eating so much oil. Also, my husband just rang me from work (I'm home on half term) informing me that it is pancake day today and he and my son would love some tonight. Ahhh, I love pancakes, how will I resist? I can't afford the syns as I know I eating out at the end of the week.
I know there are low syn/free alternatives but they are not the same and don't taste anything like them. I guess I'll just have to 'accidentally' not make enough batter for any for me.

Nope they aren't the same!!! sometimes it's easier to do without than a smaller portion,