I feel that before one adds a steroid, pro-hormone, SARM, hormone or drug to another they should have used it by itself FIRST and take notes & gain self knowledge about how that compound works in their body. Once you understand what each compound can contribute to the overall protocol you can make the decision to add them together.
Assuming you have used both the SARM and testosterone by themselves what do you expect to get out of combing them?
I don't know if Carlito is still around or if he is still meticulous & scrupulous. I know much of what gets peddled comes from those who are neither.
If you have genuine S-4 you have something that now has a solid clinical/science history. One early example, Ostarine increases lean body mass and improves physical performance in healthy elderly subjects: Implications for cancer cachexia patients, W. Evans, Journal of Clinical Oncology, 2007 ASCO Annual Meeting Proceedings (Post-Meeting Edition) Vol 25, No 18S (June 20 Supplement), 2007: 9119 gives it good safety & result marks when used in older men & women.
"Ostarine treatment resulted in a dose dependent increase in total LBM, with an increase of 1.4 kg compared to placebo (p<0.001) at the 3 mg dose. Increased LBM translated to an improvement in the stair climb test in both speed (+15.5% ± 12.9 faster time, p=0.006) and power (+25.5% ± 20.3 watts, p=0.005). There were no serious adverse events reported. There were no significant changes in PSA, sebum production or luteinizing hormone."
IF you have genuine S-4 (Ostarine) maybe you want it in you protocol because it will skew the anabolic profile of testosterone and reduce the negative impact of testosterone on the HPTA (suppressed is NOT suppressed... there is a difference in the depth to recovery). Seems like a reasonable thing to consider to me.