Dave, the problem with decoupling capacitors is that every inch counts, especially for high frequency stuff. My choice was to either simply return the devices because they didn't work or modify so they would. I think the capacitor on the wires as you suggest is possibly OK but you can never be sure.
When I get around to it, I'm going to add 1uf and 10uf to the board. As to tantalum, that's just what I had around in non-surface mount format. If you use aluminum though, it might be best to throw in a 1uf for high frequency stuff to make sure.
There's really no good way to measure this stuff. Far better to use "best practice" and add one of each size as outlined as close to the consuming device as possible. Unfortunately you can only tell if it works by lack of problems. Even if my current single cap solution is OK, there may well be other situations where the three solve a problem the single cap would not.
I put in a call to Eric but he is probably on vacation today. I have zero doubt the lack of decoupling capacitance is cause of trouble. ANY capacitance added will help. Adding all three sizes and soldering them down onto he board will help the most.
I'm not too worried about warranty. These devices look to be nearly bulletproof. By adding the cap(s) they become far mroe reliable. I'll be interested to see what UR response is to this.
