Treat them with the same respect and courtesy you would offer any other guest. By not honoring the request, personally, i think you did them a dis-service, even if you saved them money. They obviously thought you deserved a 20% tip, and it was inappropriate for your boss, or anyone else for that matter, to tell a customer that you will not accept their money. Best advice i can offer you is, treat them like a human being, imagine if you could not see, and think of what would make you feel welcome and comfortable, and if it is reasonable, do it. Do NOT bring any extra attention, and treat them like a sighted person to the best of your abilities, while possibly verbally telling them where you are placing new items on the table, that you are refilling a drink, and when you arrive at the table. The fact they asked you to help them write your tip amount shows they trusted you enough to do so. Best thing you can do next time is have your boss come over, and WATCH YOU DO EXACTLY AS REQUESTED. Now you have a person whos checkbook will not match their spending, due to the difference in what you did not take as a tip.

Sounds like you did everything right. For background, I'm a sighted man who is dating a blind woman.

First, bringing her a menu is the right thing to do, because you don't know how much sight she has. Bringing her a menu treats her like everyone else, so she isn't singled out. If she had some vision, and then had to ask you for a menu, then that puts her in an awkward position. (I've worked with a man who had a significant visual disability, but with a special lens he could read text that was very close to his face.) So "because I didn't want to assume how much she could or couldn't see" is definitely the right approach.

The only other guidance I'll offer is this: If a person brings a guide dog, just completely ignore the guide dog. Don't interact at all with the guide dog. My partner's dog is very well-behaved, but if you pay much attention to her (the dog), she'll get uncontrollably derpy very quickly. It can be stressful for the owner of the dog, when someone else is interacting with their dog, because they lose a certain degree of control over their situation, and they lose some capability, because their dog is now distracted.

Obviously you didn't do that, since you didn't mention that, but I'm just offering it because it is one of the biggest complaints of my partner, when she is out in public.

Thanks for being great, and keep it up.

My relative is now completely blind and tipping is his way of showing extra appreciation to staff who help him get around or deliver a great service. He takes it very seriously. He's also got a terrible temper and if he discovered a manager went against his wishes he would've shouted at that manager on your behalf (whether you liked it or not!) it's really strange that they would refuse to add the tip!?

Edit cos I just remembered something funny, often when he asks people a question about the food they'll point at the menu and start talking about it, and he'll shout 'i can't see the bloody menu pet, I'm blind remember!' and they get really embarrassed.

Don't point at the menu if they ask a question about the menu, they probably have trouble reading it and that's why they asked ;)

From someone who can bridge the gap between serving and visual impairment. inpairment.

-Do ask their name. This will help allow you to let your presence be known at the table without adding awkwardness.

-don't ask any specific questions pertaining to the impairment, its rude and as irrelevant as what time to the specific second the neighbors let the dogs last night.