Thanks for those words.  I tried:
 
b l o c k c h a i n  Driver Version 17.30.1029
Crimson ReLive Edition 17.7.2
Crimson ReLive Edition 17.11.4 Optional   *currently running
Adrenalin Edition 17.12.1

Have learned, in all above driver cases, -fanmin does not behave the same as Claymore ETH miner.  Manual fan control using wattman is required for me with Claymore ZEC miner, but at least fans can be controlled.  Did not have to do this with ETH version.  Maybe its my vbios customizations having negative effect in zcash mining but not eth mining..  I don't know..

Also learned wattman has new feature to select 'compute workloads' instead of 'graphics workloads', but I only seem to be able to activate it for 4 gpu.  Difference seems to be a couple degrees less heat in compute-workload-enabled cards.  Hash/sec is within 0.1% across cards.

Also have taken to stop/restart the miner about every 12 hours, and have not suffered hang/reboot in last 48 hrs.  

Avoiding miner hang/reboot is good because wattman loses all settings.  And since wattman settings are lost, I cannot automatically restart miner (because no fan control.)

edit: suspicious link fixed

My experience is that compared to other Claymore miners, this ZEC one seems to be least stable in current version. 

Not simply complaining; I am grateful to have good miner, and happy to pay for it with Dev Fee, because = stability.

Running 8 gigabyte RX580's, Win10, various drivers;  I have mined 30 days solid using latest Claymore Dual, mining for ETH only, with zero problems.  Fans are well controlled, as is temp.  No reboots.  Using miningpoolhub with no problems.

With this ZEC miner on same hardware, the miner does not last more than 8-9 hours without reboot due to miner hang.  While mining, it gets 2.3MH/s at flypool on average.

Have not tried debug log level yet..  Logs do say: "watchdog - thread 31, hb time 0" then the reboot.  This does not show in logs every time, for every reboot. 

Have reduced intensity from 6 to 5, no difference in reboots, but can see the difference in reported hashrates at pool. 

Have tweaked gpu and mem clocks to be conservative and as even as possible; and also tried larger ranges between each card.  None of cards are overclocked, all are underclocked or zero clock changes using Wattman.  (I burn the values into each VBIOS.)

Other weird things I noticed, maybe have no meaning and just flake; 

Using the -mport option in any form, it caused immediate loss of fan control to the miner (eg -fanmin 50 no longer had any effect). 

Sometimes the reboot seemed to come after Dev Fee mining sees a stale share. 

Sometimes reboot seemed to come after >5 stale shares. 

Checking hashrates and % invalid at pool, the qty of invalid shares is to good shares is 0.02  -  0.03%  - so it is not like crazy overclocked, with high number of rejects; I guess qty of invalid shares does *not* seem tied to reboot.

On MPH, you make a wallet for each coin you will mine.  In that wallet screen, you give the address where payments will be sent.

Auto-exchange lets you mine coin-A and MPH swaps that for coin-B, into your wallet, then paid out once the threshold is reached. 
You need wallets for each coin - each must have a place to land.  (i think.)

I guess auto exchange is useful if you want/need to end up with coin that you cannot mine natively. 

My experience with multi-coin was neutral.  Tried ETH+SIA with Claymore.  Was not as fast as single coin mining, and I did not want to hassle with exchanging SIA for something I can trade with.

Just some words for noobs or people coming to MPH from Nicehash.  MPH has been super reliable for me.  No problems with payouts, they are always on time, for the amount expected.  Thanks to MPH for being reliable in this time of more and more sketchy pools.  Disclosure:  I donate to MPH.  Why?  Support, and reliability.  It's worth it.  I don't worry about the dashboard - it is nice to have but not critical to the function.  What is critical is getting paid.  And MPH has done that for me, predictably.

The fact that a bunch of miners would be moving from Nicehash to MPH did not occur to me until just now.  But yea, I guess it is large quantity of new traffic on MPH.  So, free advice that you maybe did not want:  take it easy, relax, mine one coin at one time, and set target payout low (and frequent).  

Now to my problem - anyone have any info on Dashminer.com pool fail from Dec 8?