Bad idea...
I have some experience using this product therapeutically in animals as a veterinarian. I can tell you right now that you'd be a fool to attempt it.
This is an ultrapurified bovine hemoglobin product that is carried within the plasma portion of the blood rather than within the cells. So you're right that you will increase your oxygen carrying capacity without increasing your hematocrit. It is used in small animal veterinary practice to treat patients with severe anemia.
There are significant drawbacks to use of this product:
First of all, it is quite expensive and difficult to obtain. The manufacturer has spent years and millions of dollars attempting to obtain FDA approval for use of the product in people and has nearly bankrupted itself in the process.
As far as "undetectable" status goes, once the product has been infused the plasma has a dark red to purple "hemolyzed" appearance.
Finally, every species reacts differently to the infusion. While it tends to be well tolerated in dogs, it can cause fatal pulmonary edema (fluid build-up within the lungs) in cats even at small doses.
You'd be far better off training at altitude, I can assure you of that!