that's called martingale, and I would never call it safe. here's a fantastic strategy for you op, just stay off of dice sites.
I guess it is safe enough if you do it slowly, like set the max winning. 0.01 per day is great amount if you can manage it well so stay off from dice site is not a good idea since you can earn much from dice site. Usually I use martingale or roll manually, depends on my luck
i have been using a lot of martingale strategies lately with a somewhat big bankroll and starting from 0.00000001 BTC and with different sorts of multiplier to have lower or higher chances of wining and as a result different increases to cover the loses .
but in dice martingale no matter what sort of martingale strategy i choose i always end up losing more in just one second where i roll all reds.
all strategy are going to lose in seconds or minutes coz eventually you're going to hit a bad luck.. Its just calling when to stop and get out in profit..