The basic ACOL principle: Every 4 card is biddable and you start with the lowest one. This will give you some awkward rebid problems. What to rebid with KJxx xxx AJ KJxx after 1 1? ACOL says rebid 1. Partner most likely says 1NT, end of auction resulting 1NT in the wrong hand. It's much better to rebid 1NT with all balanced hands (11-14) and ignore the 4 card major. If partner has less than invitational 1NT is often the best contract even with a major fit. With invitational values or better you still can find the major fit with (two way) check-back Stayman. As a consequence of this approach a sequence like 1 1 1 also means a unbalanced hand (most likely a 5431 distribution). You can also perfect this sequence even more with a direct 3 card support and a 4315 distribution (1 1 1 means now partner I have just a singleton support). You can find out a real fit later with invitational or better values. With less you end sometime in a 4-3 fit hearts, but remember the 3 card heart hand is unbalanced with ruff potential.

xx45 xx44  4441          

More ugliness appears with (11-14) 4 diamonds and 4 clubs or even 5 clubs. If you open a club and partner respond with a major, what is your rebid? If balanced you can bid NT but unbalanced repeat clubs and promise 6, reverse to diamonds? Its just ugly and even simple so resolve, just open a diamond with those hands. If you do face yourself with a rebid problem you could always bid clus, ok you promise a 5/4 in basic ACOL, but at least you have told 8 cards in two suits, way better than lie extra club-length or lie extra strength. With stronger hands you still can open a club with 5 clubs and 4 diamonds because you can reverse now.

In a lot of systems there is room to deal with 4441 hands. Mostly they have incorporated special relays or even special openings dealing the problem. Why? 11-14 4441 hand only occur in 0.9% and 15-17 only 0.3%. Just open a diamond (unless it's you singleton than open 1 club) wait for partner and support him like you have a 5431 hand.