perhaps a handful of big solo miners found out that it isnt profitable to solomine so they turned to pools or people who found out that thanks to the difficulty increase, its no longer profiable so they turned off their asics
Very few, if any asics would be turned off at this point. The vast majority is still at least marginally profitable, and even if they werent, they would be sold and start hashing elsewhere. What has become unprofitable (gpu's, fpga's,..) is so marginal in hashrate that you wouldnt notice it.
Now it is possible some big solo miners joined pools, but that still leaves me slightly baffled that the hashrate is seemingly flat or a tad down when, bitfury and KnC (and in all likelyhood, even BFL) are constantly adding significant amounts of hashing power.
