This should work better than a can of Framesaver with a 10cm rigid tube. Dinitrol applied through a long flexible tube may work very well for bicycle frameset rustproofing. AFAIK Dinitrol is not sold in USA and I have no experience with the product. The material is of less concern than the method of application and the probability that the application method will coat all surfaces.

Linseed oil has an advantage of being an inexpensive low viscosity liquid ($10 per liter). When rustproofing a frame, one tube at a time, pour in an abundance of the liquid, plug all holes into that one tube, then distribute the liquid with slow, deliberate, repetitive bicycle frame movement. Drain the liquid, move to another tube, repeat process. Except for the headtube and seattube, it is impossible to inspect the work (maybe with a tiny endoscope), but if you have plenty of liquid sloshing around as you slowly rotate tube, then you can be reasonably confident all the steel surface has been coated.

With an aerosol application from a spray can, it is less clear what exactly is being coated inside the tube. I would have to use $50-65 worth of Framesaver to get the same level of confidence (and rustproofing) I can achieve with $5 of linseed oil. This is what Bob Jackson appears to be selling, with the significant advantage of a long tube for delivery. The tube may be too large in diameter to fit into chainstay, seatstay and fork vent holes. I use a grease gun needle to deliver linseed oil into the small holes (attached to a pistol oiler with tubing).

There is no benefit to higher rack. Higher rack simply raises center of gravity which may affect bicycle handling depending on load. It is a detriment, not a benefit. Salsa had to make a whole line of short racks to fit their bikes with Alternator dropouts, because a Tubus or any other conventional rack sits too high, in turn making the panniers ride high.