Do settlement rules apply?

Client is director of company and nearly higher rate tax payer (he has separate employment income from an unrelated

employer). His business partner is also director. They held 50 shares each.

My client, one of the directors, gifted 25 shares to his wife (lower rate tax payer). She has little active involvement in the

company.

All shares have equal voting rights and client is content with commercial implications of gift (eg of minority shareholding).

Dividends are paid to separate bank accounts. 

Arrangement appears secure as comprable with Arctic Systems.

Client now wants to give further 15 share to wife (to benefit from her basic rate band). 

I feel uneasy about "diverting" more than 50% of dividends that HMRC might expect him to benefit from.

But if he is free to give 50% of his shares to wife and avoid Settlement I assume he can choose to give 75% (or 100%!)

and use the same defence?