Day trips to Weymouth '22 - do I have this right?

Summer day trips by train - Melksham to Weymouth

The Off Peak DAY Return via Yeovil ticket costs £20.30 for an adult and £10.15 for a child. Children under 5 travel free. This ticket is valid on the 09:10 train and anything later on Mondays to Fridays (so not the 06:36) and on any train on Saturdays, Sundays and Bank Holidays.

Other (higher priced) return tickets are available if you want to stay in Weymouth and travel back on a later date, or make longer journey that doesn't go via Yeovil to get to Weymouth (you might want to do this if there's a long gap in services or would be a long wait at Westbury for a connection)

Monday to Friday (not 18th August)
09:10 from Melksham. Change Westbury (09:26 to 09:32). Weymouth 11:00
17:30 from Weymouth. Change Westbury (19:12 to 20:06). Melksham 20:21

Saturday (not 30th July nor 20th August)
08:34 from Melksham. Through train to Weymouth arriving 10:24
(later trains with good connections at Westbury at 09:06 and 10:00)
19:40 from Weymouth. Through train to Melksham arriving 21:32
(earlier train from Weymouth at 16:10 with connection at Westbury)

Sunday
09:40 from Melksham. Change Westbury (09:54 to 10:22). Weymouth 11:54
17:53 from Weymouth. Change Westbury (19:34 to 20:24). Melksham 20:39):
(earlier train from Weymouth at 16:10 with connection at Westbury)

Now - let's look at Groupsaves an other card schemes.

* If you are travelling in a group of three or more, you can ask for a GroupSave ticket and that will give you 34% off off peak fares but (new rule) not before 09:30 on Mondays to Fridays. So in practice, this mean that thre adults travelling together will pay a total of £40.05 on a Saturday or Sunday, or £60.90 on a Monday to Friday as after the 09:10, the next train does not leave Melksham until 11:31 and (after a wait at Westbury) get you to Weymouth at 14:06.

* Your group of 3 could travel on the 09:10 on Monday to Friday with and a Groupsave off peak return from WESTBURY to Weymouth at £41.25 plus £13.20 for three off peak day returns from Melksham to Westbury - total price £54.45 rather that £60.90

* Holders of Senior Railcards can also get 34% off, and that's not time limited to 09:30, so they can travel for £13.35 each on the 09:10 as well as on any other off peak train

* Holders of Senior bus passes can get 34% off Westbury to Weymouth tickets after 09:30 and any time at the weekend, so they can travel for £18.15 each even if they have no senior railcard. (also buy a Melksham to Westbury off peak day return)

If you hold other railcards, please ask / check on validity.

Q1: Could a party of three on the 09:10 on a weekday buy a Melksham to Weymouth Groupsave 3 from Melksham to Weymouth at £40.05 and three off peak day singles MKM^» to WSB^» at £4.30 each (total £52.95 rather than the £54.45 that I suggested above). Bit loathe to suggest that as I'm only 90% sure it's valid!

Q2: $64,000 - how can I explain all of the above in just a few straightforward words?