I think it depends on what the issue is you are trying to solve. If platelets are in normal range and just red blood cell count is elevated, I don't see how a double red donation is a bad option.
"Normal range" platelets doesn't mean you are safe from clotting, in fact, there is no reason to think anyone would have above normal platelets, even if they threw a clot. The problem isn't the level of platelets, the problem is the red blood cell count and the INCREASED platelet count from giving away 20% of your RBC and none of your platelets (they put most platelets back, not all), they also put back some saline to make up for the missing volume, but this doesn't stay around. The end result is a short period of time where you are at an increased risk for clotting.
Here is the thing, there are many, many factors that control clotting. You could easily have normal crit and normal platelets and throw a clot. The body is in a delicate balance, and taking AAS (ie stimulating epo production) throws that balance off. We are looking to correct that balance to prevent the risk of throwing a clot (also maybe to make the heart not work as hard). So if you are out of balance, I would suggest not giving double reds, which further throws the body off.
This isn't my "theory" this is the advice of several doctors I know who specialize in this kind of stuff (although not a hematologist). Remember, doctors deal with this constantly in patients with CAD, COPD, etc.
There is also a "rebound" effect after giving blood where platelets temporarily rise (even with whole blood), combine this with putting platelets back, and you could have an issue.
There are many other reasons that are over my head that go into the recommendation by "alternative" doctors to always give whole blood.
My woman does this for me bi-monthly.
It's fairly simple, everything is sterile & I have not had any issues aside from trying with too small of Ga needle the first time.
She is a medical pro(well, about to become one). Without her, I wouldn't be able to do it myself.
Works out well, much less of a hassle than trying to go in. And sometimes we do it more often(depending on my cycles).
To anyone who straight does their own - you have balls of steel. Because it is possible to pass out - you have that shit still stuck in you.
Do you monitor your crit? Too low of a crit could seriously impact your performance, bi-monthly donations would lower crit way too much in many people.