I don't know if test inhibits collagen synthesis, though it's been suggested, and at supra-physiological doses I doubt it's well characterized. What is certain is that on cycle your (muscular) size and strength grow at a high rate, leaving your tendons and ligaments as the weak link.
Estrogen definitely plays an important, positive role in the process. A quick Pubmed search pulled up this article ( http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2674543/?tool=pubmed ) which
is a decent review of the effects of E & T, though it involves seniors, not young weightlifters. The included references might prove useful.