It's theoretically possible, and can work with a noticeable impact however the general idea and principle of starting out with a faster acting substance Orally is to proverbially jump-start the Cycle before IM Injected Substances can fully kick in.. So doable? Yes, feasible and worthwhile? Sure, just not I suppose the "ideal" depending on what you're looking for, you're certainly not fucking up by doing so
Regards
Max