Ive read a lot about guys being worried using gels in case of transfer to family members & while I always thought this slightly paranoid due to my own experiences using testogel, I saw this article that might be of interest:

"Although considerable amounts of testosterone remain on the intact skin for several hours after evaporation of the alcohol vehicle, contamination of a second, especially female or prepubertal, subject causing side-effects seems very unlikely."
Document Type: Research article

DOI: 10.1046/j.1365-2265.2002.01529.x

Affiliations: 1: Dr August Wolff GmbH, Sudbrackstr. 56, D-33611 Bielefeld, Germany.

This is an excerpt from an actual experimental study, not just a theory!
I think the manufacturers are always going to give any possible dangers however remote just to cover themselves.
Anyone using T gel will know its just not that powerful!