yes I've never understood why people do up pedals and bottom brackets so tight. You just need to 'nip' them and job's a good'un...
I've never had one undo itself that I've tightened myself and they all come undone dead easy.
I am guilty of tightening up bottom brackets a fair bit as i had one slacken off and wreck the threads in the frame BITD, always grease all threads though.
Also totaly knackered a 1 1/4 treaded headset BITD by stopping at a garage ten miles from home to ask them to tighten it up, the mechanic used stilsons
I now have the proper spanner for the 1" headsets in my Oranges, also decided a while ago to stop battering headset cups in with a mallet
Going to either make or buy a press. Recently invested in cone spaners too.
You can remove some flat pedals with a normal 15 or 16 mm spanner but most need the proper thin one.