I've got a Z-Force 44 and feel the same about the deck wash fittings. I did use them awhile back in the spring and early summer but they never did completely clean the deck whether the grass was light or heavy. I haven't pulled the deck off yet. Not sure if that would stretch the big belt by taking it off and putting it back on. I usually drive the front of the mower up on car ramps, lay down beside the mower and, with a few choice words of course, clean the deck. It's a little time consuming and messy but effective. Also, the mechanic at the tractor place where I bought the Cub recommended against using water to clean it. Said there was too much of a chance of water doing damage to the mower if it wasn't completely dried before putting it up.
I had an old Snapper rear engine rider before this and it would clog some too but I could at least pick up the front of the mower and lean it back on it's frame to clean it. A little heavy but much easier to clean.