WP API keys: does it now generate just 4 values?

I hope this is the correct forum for my question, so here goes: since the late WP2.x series, the v1.1 API key generator randomly creates a series of four keys (AUTH_KEY, SECURE_AUTH_KEY, LOGGED_IN_KEY, and NONCE_KEY) and four salt values (AUTH_SALT, SECURE_AUTH_SALT, LOGGED_IN_SALT, and NONCE_SALT).

However, it seems recently the generator is back to generating “just” four, and not the eight (if I remember correctly) that it used to create. The questions are:

• Is there a particular reason for that reduction to the four keys originally introduced in WP2.6?
• Are the four salt values redundant, i.e. does it matter to have them defined at all with randomized string values?

Thanks in advance for the clarification!