Appointment of PM and passing the budget is set up to make it easy for minority governments. Legislation still requires a relative majority to pass. But with a very proportional distribution of seats and no direct election of the executive I think that is a rather an advantage that the system can work without a majority. For example in 1978-9 the parliament appointed Ullsten (liberal) as PM with 39 votes for (liberals), 66 against (conservatives & communists) and 215 abstaining (soc-dem and centre). Parliament was split in left and right, but also in pro-nuclear and anti-nuclear, which made a liberal government the least disliked option. Of course they had to build temporary coalitions to pass anything.

Swedish MPs rarely stray from the party line, and never when it matters, but I think that has more to do with strict control over nomination lists and a weak element of preference voting. Together that makes straying from the party line a quick way to end your career.

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