Hi Bugsy,
Who is going to notice "discrepancies" - and what are they in any case ?. They're just nuances which make you feel closer to a song and we all do it whether we're singing, this, that or the other.
We do it to personailse it ,to make it feel comfortable , like an ould jacket or a pair of jeans and from the moment you start to perform it (any song by the way) you put YOU into the delivery to your audience whether it be to a house full or to a grandchild who needs quietening down with a little song.
May I wish you lots of fun and great choruses in your "deliveries".

Cheers Betsy