Bleach works better when mixed with water. That is not just me saying that, it is a proven chemical reaction. A stronger dilution will probably workjust as well, but not straight bleach. Any alcohol will work, including gin and tequila.

1+9 saves time and chemical. Its just a balancing act to get done and get on to other things. Less works, we use a very tiny amount of chlorine in drinking water for example, but it sits around for a really long time compared to a few seconds of tool washing.