Yamaha's web site says it is 0wt and there are a lot of threads out there debating what it is. One guy called eight different suspension shops and got answers from 0wt to 15wt. And there is no good standardization of fork oil weights which is probably why there is so much confusion around these topics.
I use this resource when substituting aftermarket fork oils for OEM oils:
It lists Yamaha's 01 suspension fluid and the precise viscosity of other oils. (Note that there is a Castrol 10wt with lower viscosity and several 2.5wt oils of higher viscosity.) 5wt Maxima is readily available and looks like a good match.
I'm working off the data I have and the professional who helped me with mine and am confident in his work. He also indicated that there are wide disparities in true viscosity versus actual. I am using Maxima Race 5 weight now.
Sooooo.... your chart for Red Line show a 70% 5wt and 30% 2.5wt (3.5wt?) is just about the same as Yamaha 01. Sounds good but I had an issue a few years back with my R6 track bike. I was told then that the 01 was 5wt. Three laps into the first session of my next track day the bike was almost unridable. I had the on site suspension guts tweak the forks. They went full hard on the compression. up on the rebound and up a bunch on the pre-load just to make it work. This helped a lot but was still far from good. I changed out the oil the next day for 10wt and it was more or less back to normal. Granted I don't recall what brand of oil I used but I'm trying to avoid that mistake again.
Have you tried the Red Line mix in your S10?
I'm a fan of Red Line products ::012:: and would like to use it but like I said I'm trying to avoid the "testing" if I can. ::010::
Sent an E-Mail off to Red Line and they got back to me, right away, and also say there light weight 5wt is the cross for the Yamaha 01 fork oil. Guess I'll use that here soon to change out the fork oil.