No. First of all, hair can't be "trained" to be straight. That's called heat damage, and that's irreversible. Thermal heat and flexi-rods/bantu knots are two completely different things, and neither of them can make the hair "remember" the curl pattern (or lack thereof in the case of straightening.) Besides, your hair doesn't have any kind of memory. If it did, we'd go up to day 365 with twist outs