terry to tel is an easy one- english, being a lazy language, tends towards abbreviations. and if you try to abbreviate terry tel is the closest syllable to ter, which is uncomfortable to pronounce. gary/gazza etc. is a liverpudlian thing more than anything, and slightly strange as the lazyness rule doesnt apply. it does, however follow the law of consonantal shift, i.e. that over time consonants soften...bs become vs that soprt of thing
I think its rooted in affection. My name is Andrew, I prefer Andy, but family and close friends call me 'And'. My youngest daughter is Charlotte, has always been Charlee, but to various of us, she is 'Charles' I think most additioanl abbreviations of shortened names are simply a further familiarity, which i think is rather nice. The notion that we 'know' public figures tends to encourage this trend.
Thank you both for your replies - from two different angles. I hear the 'azza' all the time - and we're down on the south coast incitus, so it travels well. I'm not patticularly fond of it especially when it's used for hubby's name, but grin and bear it as it's as you say andy - a term of affection. :-)