Can I use present perfect with 'once a week'?

Question

George Hummel usually _____ with members of his department once a week to discuss schedule changes.

a) meeting b) meet c) meets d) have met

The answer is c, Ok,that's easy. But if I change 'have met' into 'has met', is this sentence correct, especially in grammar? So my question is;

George Hummel usually has met with members of his department once a week to discuss schedule changes.

Is this sentence correct? As a non-native, I'm often confused in using present perfect. So, Can I use present perfect with 'once a week'?

Answer 1

Present perfect is permissible there, to describe a practice which has been in effect up to the present moment.

Reporter: Will Mr. Hummel continue to meet weekly with members of his department?
Press Liaison: Mr. Hummel has been meeting with them once a week, but going forward he may meet with them only once a month. How often they should meet in the future is the subject of today's meeting.

There, the present perfect continuous reinforces the idea of a situation which has been ongoing; the tense corroborates "once a week". But we could also say:

Mr. Hummel has met with them once a week...

to express much the same idea, the difference being that in the present perfect has met there is no sense of recurrence. The phrase once a week alone expresses that idea.