On the Oxandrolone's effects on T3/T4 levels, this is from oxandrin.com:
"... may decrease levels of thyroxine-binding globulin, resulting in decreased
total T4 serum levels and increased resin uptake of T3 and T4. Free thyroid
hormone levels remain unchanged. In addition, a decrease in PBI and radioactive
iodine uptake may occur."
I am gonna start an ox only cycle soon and I'm considering throwing some tiratricol into the mix, just in case.