With an average ilvl of 342, I have 16% hit and 19% crit. Granted, my haste and mastery are quite low, since the little that appears on my gear is all reforged into hit and crit, and I also rely on a trinket for a good deal of my hit rating. I could theoretically glyph for molten armor and drop a percent of crit to reach both hit and crit cap.
Then you have a lot of loot luck. Here is a rough table with the item points per 346 item (note: these values are rounded and approixmated - but you will find two secondary stats with roughly these values on 346 gear:
main hand| 100
off hand| 112
So this gives you roughly 170+112+130+112+200+112+100+112+60+130+130+150+200+150+112+270 = 2250 (2632 with two trinkets and rings) available points from gear. So if you just have crit/hit on gear it is easy to reach the 1742 for hit and ~2000 points for crit. However the moment you get gear with haste and/or mastery (and there is a lot of gear with at least one of these stats out there) you lose 60% of those values.
So for eaxmple haveing feet, wrist, shoulder, waist and trinkets without the desired stats gives you: 2250- (150+112+130+150+270) = 2250 - 812 = 1438
Now you can reforge and save 40% of the stats 812*.4 = 324.8 and 1438+324 = 1762 which would push you just over the hit cap but under the crit cap.
Of course gems and enchants make it easier, but as soon as you have 7-8 pieces of gear without hit *and* crit a secondary stats it gets difficult to reach both caps.