There are two situations to analyze here: being benched and getting paid a lower salary. Both of them have problematic implications for employers and employees.

Here is what concerns me. As far as I know, it has never been done so far, but the possible consequences of being benched are that the I-485 can be denied and (POSSIBLY, but there are strong arguments against it) I-140 could be revoked if already approved. If I-140 is not approved, USCIS could easily deny the I-140.

Quote: (1) If we revoke their H-1, are we still required to pay full wages if our clients say they do not currently have a project for our employees?

Ans. You are not required to pay "bench salaries" for employees whose H-1 are revoked (remember you must inform CIS and offer employee a one-way ticket home). But we then have exposure to the questions, "do you still have a "permanent" job for them?" If the answer is no, then their GC processing can be interrupted unless they use AC21 portability.

1. She can NOT do this on H-4. Once you folks file 485 and get EAD, things will be different.

You can then be a passive investor (performing no work type activity for the company) even while on H-1. You can also be an active investor if you wish to move to EAD as long as you maintain your intention to work full time for the GC sponsoring employer. Your wife can work for the company, own it, be partners, etc. as long as she has the EAD.