ª A 10 5 3
© A Q J 3
¨ 10 4
§ 10 5 2
© 10 9 8 7 4 © 6 5 2
§ J 8 7 6 4 § Q 9
ª K 9 7 6
¨ A K Q 8 6
§ A K 3
Let's suppose North passes and South opens 2 Clubs as the writer suggested. North responds 2 Diamonds, waiting, and South rebids 3 Diamonds. North stops to think. He knows that partner has 7 Diamonds with 21 points, 6 Diamonds with 23 points or 5 Diamonds with 25 points. He has adequate support in the first or second instance, but not in the third.
North hesitates to rebid one of his 4-card majors or 3 No Trump lacking a Club stopper. He'll probably decide to bid 4 Diamonds, hoping that partner has a 6- or 7-card suit. He will probably figure that even a 5-2 fit is better than a possible 4-3 fit or worse in a major or No Trump lacking a stopper.
South figures partner for adequate support and extra values since he didn't go straight to game. He might use Blackwood and get to 6 Diamonds, but he may be cautious with his minimum values and uncertain singleton King. A difficult sequence to navigate.
Let's suppose that South instead opens 1 Diamond. If North can't respond, they probably don't have game anyway. In this case, North will respond 1 Heart and South will jump-shift to 2 Spades showing two suits, 19 or more points and forcing to game. North will stop to think. He sees a good fit, at least 30 points and his support may make partner stronger. He figures that if South has extra values the Aces will take care of themselves, so he jumps to 5 Spades to invite slam.
South promised 19 points and now reevaluates to about 24 with the good fit, Heart support to bolster his singleton King and a good 5-card side suit. He goes happily to 6 Spades or maybe 6 No Trump. He needs careful play for 6 Spades, but takes them all in No Trump.
Some players like to open 2 Clubs any time they see 22 HCPs, but that is often unwise. In this case, I would call it misleading and awkward.
Keep playing and sending those questions. I can guarantee that I'll always do my best, but I can't guarantee that I'll always tell you what you want to hear. Stay well, Dave