Perhaps the fish in my venues (mostly roach) are not as fussy as some in other places as I've never found the need to microwave, or do anything else to a standard slice of bread, for that matter. I buy Warburton's medium and keep it in the freezer with the only 'must' being it is kept well wrapped at all times. Any exposure within the freezer will dry it out and this not ideal, although I have used when pushed.
I take out a couple of slices, place it in a sealed bag and keep it well covered during the session and that's it. Any leftovers go towards the liccy...............
I am not a punch 'expert' by any means but I do catch well on the stuff, providing the liccy or slop is well prepared and the tackle set-up is sound. It's a very, very simple bait and a simple approach has usually produced results. I can appreciate matchmen and other regular users might find certain 'improvements' help when it gets tough, though.
Not to say other ways would produce even bigger and better bags, but why change a winning method...
ps I do use the (Jerry recommended) Drennan bread punches, various meat punches from time to time and they all produce fish, but I do have a preference for the standard punch and fine tackle fishing.