Mahonia - 6ft tall and all stick with tuft of growth on top - can I rescue it with hard pruning?

[pepperrabbit]

I perhaps should have done something about this several years ago
Can I prune hard after it flowers this spring?
There is one lower growth branch but nothing within 2ft of the ground that would count as a shoot. It's in a bed I have lost control of really between a forsythia and a dogwood.
Google is confusing me some pages say late summer some say spring for pruning.

There are youtube videos that show you how to do this. I am crap with links, but just enter "hard pruning mahonias".