Yep - I do tend to undo wire brushed with a suitable spanner to save pricked fingers. But everything else, by hand, on the disc, standard nut.Having misplaced the boss key/spanner to undo the standard nut on my 4 inch angle grinder after I'd unplugged it
In desperation to finish the job I locked the spindle & pulled on the disc anti clockwise .. it undid the cutting disc as the nut slacked off .
That was about 11 years go . I've tightened and undone them just by pulling on the disc's ever since. Both on my 4 and 9 inch angle grinders, using resin fibre disc's, tungsten & steel disc's , flap wheels and wire wheels when wearing gloves . So far I've not had one slip or break up on me .
I eventually found the boss spanner some months later on the floor under a bench where I'd no doubt kicked it ..