Yes - but only a few weeks ago so can't comment on growth. I would expect it to grow as you hope, ie thicker. They're often grown as street trees here. I know of some planted along a busy road - buses and large trucks speed past and brush up against them - they grow oddly with a flat side towards the road and normal rounded side towards the footpath.
I reckon you can do anything with them.

Proteaceae usually love a prune. I'd go bloomin' mad with the pruning saw & secateurs.
Tony

Used a lot as street trees here too and the council often get stuck into them and sort of topiary them. I'd say go for it, too.

Hi. As an aborist, I cringe at topiary pruning. It can be done, but the tree should then be kept to a height of less than about 8 metres for its life, as the regrowth should not be allowed to thicken to a point where it presents a danger.

My reasoning is that regrowth branches, called watersprouts, do not have a good join to leaders like natural branches and are more prone to failure. Here's a link with more about the aboriculture of ivory curls