CLAUDE VS CHATGPT: WRITING AND REVISION EXERCISE
Original fictional brief. No native app outputs or rankings are supplied.

SOURCE
Delivery moves from Tuesday to Thursday. The agreed price stays USD 2,400. A technical review is still in progress, and the cause of the delay is not confirmed. Do not blame a supplier. Ask the client to confirm a 15-minute call on Wednesday. Thursday is the current plan, not an unconditional guarantee.

FIRST REQUEST
Write a client email of no more than 120 words from this source. Be direct and considerate. Preserve the price, revised delivery day and uncertainty. Ask for the Wednesday call. Do not invent compensation, a cause or an approved guarantee.

REVISION
Make the email warmer and shorten it to 90 words. Keep every factual constraint and the call request. Do not turn the planned delivery day into a guarantee.

METHOD
Use the identical source and requests in fresh native Claude and ChatGPT conversations. Record app, date, plan, visible mode, complete outputs and any extra requests. Count factual errors separately from tone preferences. A different account feature is not evidence of a smarter model. Keep unavailable and not run distinct from failure. The accompanying worked example is editorial teaching material, not an output from either native app.