Try digging oneor two up.
Check for firmness.
Cut in half and check for maggots.
We had this problem but it was caused by very healthy bulbs just being too congested.
They needed lifting and replanting with more room.
Depends on why they aree blind. If like us you are inflicted with Narcissus root fly, then dig them up and burn. You can tell if it is this if the leaves are few and weak growing. Dig up a bulb and if it is soft then cutit open and you cannot miss the slug like beast in the centre.
If the leaves are green and healthy and the bulbs were planted at the correct depth, then leave them in. Feed with a good foliage feed and split the clumps if they are crowded. They are like any other plant they do need some looking after.
Great advice Berghill. I've not experienced Narcissus root fly before but I'll certainly try to remember what you've said. I've always left foliage on to die down completely (never do the tying up with string thing ) and give them a feed so not had much bother with daffs but congestion does seem to be a common problem for lots of people- and easily solved!
Sometimes it's just due to the weather at leaf dying down time the year before.