For Clumsy Musical Whistle Challenged Like I, who has uncoordinated fingers has any one thought of this ?
Placing a small ring of silicone around the holes so it makes it easier to find the hole with your fingers plus it makes sealing the hole easier.
I suppose gluing a small rubber O-Ring around the hole would do the same thing.
Always looking for a easier way, BTW I’m sure the silicone dosen’t do anything for the tone, but at this point I’m more interested in the rythrm and such.
Bob 
I made a low C whistle and put O rings on each hole. It was very easy to cover and seal. But I think most whistle buyers would not like the appearance. I also made a low D of pvc pipe and filed low places around the holes to fit my fingers. There again it worked great. Fingers fit in fast,
and did not have to undercut the holes to tune it. I polished the recess around the holes but still I think most buyers would not like the apperance. I do think they would make a good learning whistle to start with so a person could play sooner. Then buy a nice normal looking whistle. They did help me learn to play a low whistle and now I have a Howard low D and an Overton low D. Low whistles take a differant breath control than a high whistle but it can be learned, and if the holes can be found easy the breath control can come sooner. But I don’t think I would want to show up at a session with O rings or groves around the six holes.
Another thing that helped me was hand lotion. Soft skin makes a better seal on the tone holes. Just don’t put to much on your thumbs so the whistle can still be held.
I’ve made a few Whistles with fairly thick (2mm) plastic tubing and I aim to make the edges of the holes both internal and external curve into the surfaces so there are no hard edges. I did this because I read and heard from various people that hard edges reflect sound waves and can cause instabilities. The Whistles sounded good and were nice and stable in the upper octave but whether this was due to the lack of edges or not, I can’t be certain. A nice side effect is that as people have observed above, they are easy to seal.
John S