What happens if you remove randomness from Doom?

For some reason, recently I have been thinking about Doom. This evening I was wanting to explore some behaviour in an old version of Doom and to do so, I hex-edited the binary and replaced the random number lookup table with static values.
Rather than consume system randomness, Doom has a fixed 256-value random number table from which numbers are pulled by aspects of the game logic. By replacing the whole table with a constant value, you essentially make the game entirely deterministic.

What does it play like?

http://jmtd.net/log/deterministic_doom/