Role swap?

Hi, I'm usual just another dps main (mostly pranged). I haven't been playing since last December, so either way I'm quite rusty. Planning on coming back before 7.2 to prep for the next savage tier, but I had an intrusive thought while looking at my lodestone page: What if I swapped to gunbreaker this tier? Though I don't have any raiding experience tanking.

Unless I'm wrong, tanks' gameplay is more or less a glorified dps but with the need to use mits regularly (tbf you also should mit as a dps) and swap agro. My idea is to either try the EX or early arcadion savages (mostly M1), by this time barely anyone might care to efficiently clear them (I'd obviously warn that it's training in the pf description)

Sure my gunbreaker gear sucks, but by the time tier 2 releases, 730 bis will be obsolete and replaced by the new crafted/normal raid gear anyway.