We are kindred spirits Louise - I too like to look at labels and see what is in dog food. I did wonder if I was a bit sad!
Perhaps not though. I have changed my dogs' food in the past but given each one a good trial after examining the ingredients. It has always been for a good reason though. In this way I have learned about nutrition and what to look for although I am no expert.
My Cairns have just come off cold pressed Gentle which is a great food and on which they were doing well. AADF scores it highly too. The problem was that it is a dense food, therefore when you weigh it out there is much less of it in the bowl. This would be good for a dog with a poor appetite but not for mine. In addition, I could not get weight off them, despite cutting down to about 20% less than the minimum RDA. They have no treats and are exercised. Unlike your Whippet, Cairns have a tendency to gain weight, especially if neutered. They are small dogs so the weight doesn't have far to go.
In desperation I decided to try raw with one of them and, like you am using Nutriment. I telephoned the company and was told that she would lose weight if not overfed. She has been having light and low purine and after just one week lost 170g. She has only a little more to lose then it is maintenance and for the first time I am considering upping her food.
I can only assume that it is the carbs that were (as the Nutriment lady said) 'sticking to their ribs'. Two are on it now and are enjoying it. I have had a mixed delivery today so once the current cartons are finished they will have different types. Luckily they are not fussy eaters. I never ever thought that I would feed raw, despite all the stuff I have read about it. However, Nutriment makes it easy - no different to opening a can of dog food. That suits me fine.
BTW, regarding converting your friends onto Nutriment, do you know about the Friends referral scheme? Check on their website. If those people who you have managed to convert mention your name you can get £10 off your next order. I've told a few people about it but sadly, no referrals as yet.