Updating this thread a trifle.
Just had three days off without being immediately shanghaied by the other half to do some tiling / painting / gardening etc....
First time in ages to do a bit of consistent and back to back fishing and testing of stuff.
Had three lines to test
as hooklinks, Stren Microfuse (3lb / 0.10mm), Berkley Nanofil (4lb / 0.10mm) and PowerFlow (5lb/ 0.06mm).
Tested using all three back to back as hook lengths with both light float and light ledger fishing, bit of simple silver fishing. No huge fish in the lake, occasional tench up to three pounds and a couple of five pound carp or so but mainly Rudd / Roach of the 8 oz - 1 1/4lb stamp and Crucians up to 2lbs. Fishing very simply with maggots, casters, bread and (rarely) (as I have never been lucky with the stuff) sweetcorn.
Following a number of break offs / inexplicable line breaks with both the Microfuse and Nanofil I decided to do some static tests on the dining room table using a digital scale to test knot strength / breaking strain.
So the other half definitely isn't speaking to me now.
Result

.
Conclusions: Microfuse and Nanofil are both absolute buggers to try and knot. Nanofil even worse than Microfuse. Forget your half blood, grinner or uni knots. They simply pull through under stress. Knotless knot / Domhoff ? Ditto - tho the Dom was slightly better than the KK and could be used to attach a spade end. Palomar ? Nope.
If you try to tie a loop in either using any knot you like - and I have tried them all, even going as far as the fiendishly difficult Bimini Hitch - then prepare to watch both of them cut through themselves at ridiculously low tensions. Like 14 ounces or so.
To be fair, Nanofil does come with a label on the spool with a fold out section giving the only two knots that actually
do work with it. The first is the Nanofil knot - yeah, right. This miracle is nothing more than our old friend the Palomar BUT with the line passed not just once but twice through itself to form the overhand loop. This does certainly hold, but still compromises breaking strain. the 4lb line never did better than 2lb 140z, more usually breaking at or before 2lbs.
Secondly the Albright knot for joining line to line. Fine if you are putting it on the spool, but it's not really a knot you would appreciate trying to use on the riverbank to attach your hooklink to mainline.
My answer was to use a size 24 microswivel at the end of the mainline and then attach the hooklength to it. Unfortunately a moment's thought will show that you can't do this with a Palomar, whether single or double. You have to detach the swivel from the mainline, tie the doubled palomar, passing the swivel through, then re-attach the mainline to the swivel. A real faff tying two knots every time instead of one. And if your knots aren't absolutely perfectly tied then believe me Microfuse and Nanofil will crack off forthwith without giving you a by your leave.
Both Microfuse and Nanofil claim to be invisible to fish in use in the water. Frankly I can't see it. If you follow what I mean. Both are as white as chalk and opaque. When put in the water they stay white as chalk and opaque. Plus which Stren Microfuse also makes a big deal out of its ability to flouresce in daylight or under a blacklight at night. How this adds up to either of them being invisible to fish entirely passes me by.
You may have noticed that I haven't said anything about the Powerpro. Simple reason. It simply won every test category going without missing a beat.
It is the thinnest of the three lines. By quite a margin, pound for pound vs. breaking strain. That said I do not possess a micrometer, so have had to take the manufacturers dimension claims at face value.
Powerpro knots easily and well with almost all of the standard knots (sorry half blood, your day is done). Not only that, when tested to destruction it's knotted breaking point was consistently in the range of 5 - 6 lbs. Time after time after time. That's 100%+.
Plus which Powerpro did not at any stage suffer from unexpected crack offs or breakages.
Very simply Powerpro kicked the ass of these supposedly new and superior "advanced" superlines.
Anyone want to buy some modestly second hand spools of Microfuse or Nanofil.....