If they can teach, don't stop them
Now, looming retirements, teacher shortages and government policies combine to make the present restrictions untenable. It is one of the oddities of the present situation that the GTC itself warned of the "ticking time bomb" five years ago - 53,000 of 73,000 teachers on its register were then aged over 40 - while at the same time raising the barriers to entry so that secondary teachers would require to spend three years in their graduating subjects instead of two.
The key question, after all, is what makes a good teacher? An insistence that candidates spend three years studying their subject cannot seriously be part of the answer, particularly in these days of compulsory professional development.