I don’t know of any body of simulations testing this, and intuitions vary. I expect the opposite 
. The article on this I linked to before notes:
The bloc voting system has a number of features which can make it unrepresentative of the voters’ intentions. It regularly produces complete landslide majorities for the group of candidates with the highest level of support, though this does tend to lead to greater agreement among those elected. Like first past the post methods, small cohesive groups of voters can overpower larger numbers of disorganised voters who do not engage in tactical voting.
Of course people differ. For me, if I can only approve of 5, I’m most likely to vote for the 5 I’ve known the longest and best, rather than “risk” approving someone I guess will do well but don’t have that long confirming experience with. In fact I think more than a few of the latter would be reasonable choices, and so would approve them if there weren’t a limit. But, with a limit, the election is no longer asking who I think would be reasonable choices.
For us, without political factions scheming to elect cabals, I’m more concerned by possible second-order effects: if it turns out most voters are “like me” in the above respect, the quoted paragraph’s “complete landslide majority for the group of candidates with the highest level of support” will obtain, and promising non-winning candidates will be discouraged by getting very few votes (they’re on the buried end of the “landslide”). Without a limit, some number of those may see instead they actually had high (even if not quite enough to win) approval levels.