it will be more difficult to bench press with your elbows tucked in initially, as you still need to coordinate yourself with the new technique.
also, when you tuck your elbows in and keep your elbows directly under the bar, you’ll notice that your triceps get much more work that the more commonly seem elbows flared out style of benching. you will also get much more lat involvement in you can keep your eblows directly under the bar throughout the lift.
over time, i find this to me the most powerful and effective way to bench. but again, initially, there will be a decrease in performance as there will be a ‘catch-up’ period in which your triceps and lats build up the strength and coordination for this new style of benching.
personally, if you’ve just started tucking in your elbows, driving through your heels, arching your back while keeping your back and butt in the bench at all time, driving through your heels, keeping the bar under your elbows, etc… you’ve made a good decision and this new technique will allow you to make strength gains much quicker.
also, when you bench this way, you make the lift much more compound, and walk away from every bench workout with more muscles being activated than the more commonly seen flat back elbows flared out approach <which i’m assuming is the technique you were using before>… these lifters tend to view bench press as an exercise for their ‘chest days’, etc… now, you’ll away from bench days feeling more of your muscles being worked, and a better sense of how to coordinate many muscles during ONE exercise.
IMO, this is one of the best techniques for big bench pressing. you’ll also build some great tris.
hope that all makes sense.