Umiman is just the master of the universe apparently...
And wizards are too awesome for their own good.
I mean seriously, they start the game with magic resistance, two rings, their first sacrifice item is magicbane (very useful), quest is both very easy and gives the eye of the aethiopica (VERY useful), they can read spellbooks safely (and get warned if there is a chance of failure), can wear the cornethaum, and have hungerless spellcasting.
and tinning kits are useful enough to lug around, I can't tell you how much easier it is to gain strength from giants (and giant zombie/mummies) and sleep resistance from Elf zombies/mummies. Also, gaining poison resistance is much easier as the number of safe things to eat to get poison resistance pretty much doubles. Tins of Nurse meat will also restore you to full health (although it counts as cannibalism for human characters) so even though I haven't eaten it yet, I can contemplate the usefulness of not dying over the punishment for cannibalism. I always bless my tinning kits so my tins can always be consumed in 2 turns by the way. I'm just saying, if you find a tinning kit, it's more than worth it to carry one around, because proper application can make your life much easier.
I don't know why you mentioned tinning lizards Kc, because that's a terrible example. You'd never need to tin them because they never rot, and if they never rot, then you can just carry the corpse around and take a bite out of it if the nightmare that is the cockatrice ever does manage to touch you successfully.