@gailcalled – Personally I also have a monosyllabic name, but if someone adds a y or an ie to the end of it I guarantee that I will not respond except to correct them or snarl at them.
In digging further I have found that the Monks of New Skete say this about naming dogs:
“The chief rule is to pick a name easy for the pup to understand and you to pronounce. In general, we suggest, short, two-syllable names that end in a long vowel or a soft ‘a’ (for example, Nero, Anka, Ola, Ivy), because they are clear and easy for the pup to distinguish. This helps the puppy tune into you quickly and is essential later on when you are teaching obedience, especially the recalls. Naturally, you should avoid names that rhyme with or sound like obedience commands, and don’t select one over three syllables long.”
However, I can’t seem to find any concrete research that shows that two syllables are better than one or three, or that a “y” at the end makes cats respond better.
What I can find is a blog that suggests the name you give your animal at least partially defines your relationship to it. Thus a babyish name or a diminutive, such as one with a y at the end, may define better your caretaker role. The blog also says that two syllable names are easier for humans to say as well as different from commands, which tend to have one syllable. Also, that a final vowel on a name makes it easier to call the pet to you.
Another site says the name needs to begin with a consonant.
Looks like another case of “everyone says” but no one actually has done the work to prove it.