Marshall
First Post
Feel free to houserule this, but I agree neither to any "this is how the rules can be interpreted" claims nor to the "there isn't any balance or power issue" evaluation.
There arent any balance or power issues with allowing it.
WotC clearly views flexibility as a power boost in itself, and multiclassing thus carries a real cost in lowered effectiveness to compensate. This cost is not trivial, so by houseruling you need to be aware you are removing a non-trivial cost.
MC already carries a HUGE cost without having to come up with a random new implement to use it. The entire implement system is borked with random penalties like this.