After riding the Grasshopper and the rough rocky dirt sections it was clear that I needed to tighten up my corrected (read: filed) dropouts. On the climbs and out of the saddle the wheel was rubbing on the NDS chain stay. All that severe bumping allowed the wheel to move forward into it's old position. 
My previous "beer can shim" approach was not going to work long term with rough roads. You can see in the pic that I created a permanent shim. 

I roughed up and cleaned the dropout with acetone. Next, I mixed some marine epoxy with cabosil to make a strong paste. Using a mold of sorts or at least a fill guide inside the dropout I put the paste in and left it for 24hrs.

With the beer can and vent tape off here's the cured epoxy. Seems to have bonded well with the frame and even to the hanger somewhat.
Using a flat and round file I shaped and trimmed it so it allowed the plastic part of the wheel axle to fit tightly in there. Also had to file the sides since the skewer will need to clamp on the hanger/frame part well. 
It is perfectly inline now. The front sits inbetween the chain stays and the top is right between the brakes/seat stays.

(Picture from Facebook posted by Paul McKenzie).
Grasshopper Series

At the beginning it really was like a road race with lots of “slowing!”, locked brakes, the occasional exit of someone into a drainage ditch etc. The first hill sorted everyone out into groups. Lots of climbing... Some of those hills just did not stop. My strava said 8600' in 74 miles and a much of it was steep too.
I could’ve saved a bit of time at the “rest” stop. Folks generally just filled their bottles and grabbed a banana. I had my musette with some snacks. Eating was really important but for me the first time I’ve had to eat while riding. 
The dirt part was really quite tough to go fast. There were sections of gravel but most was outright MTB trails. A big 3 mile descent including some mud that would do a cross race proud. Took a while for my bike to come back to life after each section. Must’ve seen 20 or so punctures. I did feel sorry for my bike in some of the worst rocky bits. It was really making noises! Also my chain fell off three times and I had to stop to put it back on. I think if I’d put it on the big ring I might’ve been better off (thought about that too late!). The folks of cross bikes were passing a lot of people.
Amazing to see how fast the good guys can crank up those hills. I got 78th out of 156 (@15.1mph average) but pleased with my time. Definitely going to try to do all of this series from now on. Very casual in some ways (like $25 entry, super friendly people and non-closed roads) but well run and fast riders to try and chase. True grassroots racing.

Technically, the 11-28T cassette was perfect and I did not need the extra 30T I have on order but did not arrive on time (might just return it). Tubeless 25c tires were perfect too. My rear wheel did not stay true in the now slightly enlarged dropouts. I need to make it a tight fit again. 

New 'Yotes kit! This was at the start in Occidental.

Here's the Specialized Roubaix 23/25c Tubeless tire on the Belgium+ rim. A good 26mm. This is really the maximum rear. As you will see I am switching the R3 to the front. 
This tire involved the compressor to inflate for the first time. Hopefully it will hold air better than the R3. Does not feel as grippy - but then again the other tires I've been using are race ready road tires. This is a bit more endurance. I might put the 23c Ultremo back here once the Grasshopper is over. 

OK here's the Bontrager R3 25c on my front wheel (Ultregra 6700 tubeless). This is a perfect size too. Nicely paired with the back. I cleaned the bead and rim really well. I heard this is a secret to keeping these tires from losing air over a couple of days. 

Here's my problem. This super-wide HED Belgium Plus rim is 25mm wide and when paired with a Fortezza Tricomp 25c tire is measures 28.2mm wide. I am guessing the Tricomp is a wide tire in general. Feels great to ride but just does not fit the Cannondale EVO frame. It rubs on both sides when it flexes under climbing or on the trainer.
This is actually wider than my old commuter 28c Ruffy-Tuffys on old rims.

This is my front wheel setup - it came with the bike. Schwalbe Ultremo tubeless on Ultegra WH-6700 wheel. I think the rim is 20.8mm wide - not the modern wide (23mm) but not super narrow (19.8mm) either. The tire is spot on it's size at 23mm. It actually lines up well with the rim too. Prolly pretty good aero properties.

So in order to get narrower in the back to fit the frame without rubbing I took the other Schwalbe 23c tire and put in on the wide 25mm rim. It measures like a fat 25c! Perfect! And its nicely lined up with the braking surface for good aero.
Clearance is perfect to the frame. I guess When they say a frame can take 25c tires it means that it can take them on regular or regular-wide rims. The combination of the wide Tricomp and the super wide rim was too much. 

Anyways, I am pretty happy with this new setup. I won't have to keep checking the piece of tape I put on the frame for wear. I've got the max tire width. It's a good profile and I can run front and back tubeless (although I have a tube in the back for now). Also there are many more options in 23c - important for tubeless. I also run asymmetric tire pressures (since there's more weight on the back so having a narrower tire on the front is fine - it's at lower pressure anyways - plus it's tubeless so less likely to pinch-flat.  
I also found this page which a strangely familiar set of calipers. Basically coming to the same conclusion:
http://www.bikeradar.com/us/road/gear/category/components/wheel-sets/product/review-hed-ardennes-plus-sl-47670/

I also was watching a video on Sagans bike for the classics. He switches to the Carbon Synapse as it will easily accommodate 25 and 28 tires on 25mm Vision tubular wheels (and it more comfy they say). So I guess the EVO is limited to 23 or 25.

Here's another. Got a new Bontrager R3 25c TLR tire. This will be my new front tire but thought I'd try it on the rear first for a measurement. It is a much more reasonable 25c measurement at 26.8mm. That is 1.4mm narrower than the TriComp. I fitted 25mm Stans Rim Tape to convert this wheel to tubeless. That was pretty easy. This tire is tight to fit but inflated easily. See pic below for frame clearance.

Well slightly better clearance to the frame with the Bonty R3 25c. I don't think it's enough though since the wheel will flex and rub I suspect. I might leave it like this for a ride to see how much rubbing. With the TriComp 1hr on the trainer was enough to wear through the PVC electrical tape. 
Although I think on the trainer it imparts more force on the skewer allowing it to move inside the (now bigger) dropouts. I should think about how to fill those gaps to make the wheel lock in place. Some epoxy metal or something?

I applied the beer-can shim on the side I filed to make it tight again and the wheel is now firmer and centered. But you can see that there has been rubbing. Even the Schwalbe 23c rubbed a bit and the Bonty a bit more but just leaving marks on the tape. The big Tricomp actually rubbed through the tape in an hour. 
Being on the trainer definitely is worse though which I don't fully understand since the load is on the axle not the wheels edge. 

Conclusion
I will get another Bonty 25c for the front for the next Grasshopper. I might consider after putting a Schwalbe on the back (since I have two basically new tires that came with the bike). That would give me two 25c widths and a great tubeless ride with a spare of each tire as well.
It would be nice to be able to find 25c tires with a bit of tread for these mixed gravel type races. I reckon though if there was any more gravel involved it would be better to get some nice file-tread cross tires on the cross bike. So sticking with 25c slicks on the road bike is prolly good!