Zhè zhǐshì tā de rúyì-suànpán, wèibì néng shíxiàn.
This is just his pipe dream - it may not come true.
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From 李宝嘉的《官场现形记》 (late Qing satirical novel): 好便宜！你倒会打如意算盘！ ('How convenient - you sure know how to cook up a wishful calculation!'). The word 算盘 ('abacus') is the literal tool; 如意 ('as one wishes') makes it a calculation rigged in your own favor.
grammar
The verb 打 (to beat/strike) is required: 打如意算盘, never 做如意算盘 or 算如意算盘. 'Beating the abacus' is the set collocation for doing calculations.
