I really doubt that. Wallet calculations are very precise, as they take last "N" number of solved blocks, compare their generation intervals and get a mean value from that.
It means that they are free from any error factors - they truly represent hashrate power being target at a certain blockchain(still in the past).
It is far more plausible for me that liteshack devs are aware of the issue and tried to compensate(but got it wrong and are decreasing nethash). I mean there is no real way of calculating current net_hash.
Absolutely none. You can only compare difficulty of a past block with its time_since_last_block and go from there.
EDIT: Or they have a formula for each coin to lower nethash by the amount of "current_block_time / target_block_time" - It would make sense, as it would make their nethash calculations more precise.
Unfortunately in this case its working in their disadvantage, as the diff_retarget is faulty and they(as I do) assume it works perfectly.
By that argument I conclude that the real nethash for naut is in fact around 8,82 and the diff should be 7,65 times smaller to allow 1 minute block_time.
EDIT2: I think my explanation may not seem right at the first sight so here is an example:
Everything goes back to normal and naut has 1 minute block_time blocks. To achieve that either diff goes x7,65 smaller or hashrate x7,65 higher. Lets take first case.
Diff goes x7,65 smaller -> Coinwarz stays the same, as their calculations reflect the true state of blockchain. WTM now gives you x7,65 smaller hash rate, cause diff is smaller. Liteshack does not lower their nethash by x7,65 cause block time is right on target ( current_block_time / target_block_time = 1 ). Every site reports the same nethash.
EDIT3: HR did give me this link to Digibyte's post, where he acknowledges the issues and explains factors that made it possible(in general only):https://bitcointalk.org/index.php?topic=591114.msg7731756#msg7731756