Hm, now when we can build slingers I think Assy is perhaps the worst choice for toolrushing. As Emowili points out, slingers own toolarchers, especially with stone mining. An added advantage of slingers is that you can build two barracks in stone in your base so you can have slingers waiting for him if/when he arrives, even if you tool slightly slower than him. And those slingers are not wasted in bronze either - small raiding parties of CAs are swiftly killed by a slinger mob.
As for toolrushing, its quite obvious to me that the pure slinger rush is the most dangerous rush of them all. 10+ slingers can only be killed by an equal group of slingers in tool - and perhaps a bunch of scoutships, my standard defense with Hittite against slinger attacks. They eat through walls, towers etc very quickly and with stonemining they dish it out like bowmen.
My 2 cents.
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