Suppose the German Republic of 1918 had a 5 % rule, a Chancellor appointed by the Reichstag, plus a provision that to remove a chencellor other than at an electon you need an absolute majority for an alternative and provisions that early elections require a government to propose and lose a vote of confidence.
I have an idea the Nazis did not get 5% in 1928.
Plus making the President purely symbolic
Would there still have been a 1930 election?