The network total hash is not 174Mhash.

It's much less than that. What happened, I'm assuming is we had people jump on while it was profitable until the difficulty went up then they abandoned mining. This was done to maximize their profits, or an attempt to attack the coin by getting the difficulty stuck. The current estimated network hash looks too far back to get an accurate representation. I don't think the it's meant to estimate within the 48 block retarget window.

If you look at the next estimated difficulty, it's much lower because we currently aren't solving blocks at a normal rate.

Thankfully the coin retarget is set low allowing for us to easily ride out the high difficulties. In fact as of writing this, right now we are on track to have the difficulty drop back down in just over 3 and half hours with current pool hash. When it does drop the coin will become instantly profitable to mine once again. We will likely see this trend of random difficulty jumps until the overall network is a little bit more stable and people devote time and hash to it.