Taxis London

It really is going to depend on your purpose, how big the group is each time, and what your priorities are. A very personal decision. You can look at this from several perspectives. Cost, which was mentioned in your post. Convenience, which relates to crowds on the tube or rush hour traffic on the grid. Group size, will all 4 of you always be traveling together?

Perhaps the real solution is hybrid of these two modes of transportation depending on your needs each trip.

With four people the cab probably will be cheap unless there is a long distance is involved, then the Tube will be a lot quicker and maybe cheaper depending on distance. Use both.

£1.65 on the bus - can't beat that.

https://tfl.gov.uk/campaign/new-fares

Unless you are taking a cab for a journey that you could walk in 10 minutes, I have never taken a black cab that has worked out cheaper than taking the bus, my usual mode of transport in London. If you each have a daily tube ticket, again, black cabs will rarely be cheaper.

Need clarity.

Lets get down to the basics:

Are you referring to travel from site to site in London?

Or is this query about transport from an airport to where you are staying? If yes….

Are you arriving at Heathrow or Gatwick?

Where’s your accommodation?

How much luggage?

Does anyone have mobility issues?

Been traveling to London for decades. If you’ll answer the questions more than happy to offer intel.

He was referring from sites to sites within London. In his section covering Tube, buses, etc. An example we are staying in Bloomsbury area. One day we would like to go to the Tower in the morning (so lots of standing and walking there for our person with the bad back). Then we thought we would Uber boat from there down to the Westminster area and just walk around, So, using this as an example and splitting the fares four ways, we were wondering should we taxi to the Tower, then take the boat, then after wandering Westminster area for a bit, taxi back. The 60 something in our group can walk very well but needs breaks, has a not great back and has trouble standing in one place for awhile again without at least a short sit break. So while relatively fit and able to walk does need sit breaks.

Thanks

Use the Tube. Efficient and easy. Each of you will need an Oyster Card. Refundable deposit. Use a CC with no foreign transaction fees ( Capital One ) ,
put 10 pounds on each card and off you go. You tap in and out at turnstiles at each station.

If the first Underground train is crowded wait for the next. Will say some walks from where you get off the train and walk to an exit can be lengthy. There are escalators, elevators and stairs…you should also note ( although not ask strict as it was a decade ago)
that when walking up any stairs you go up on the Left and down on the Right. They drive opposite of what we do in the states and that carries over to ingress and egress.

There is electronic signage in each station staying which train is arriving at what time. There are benches to sit on as well.

Bus transport is comfortable but London traffic is abysmal.

Born when Truman was in office. Nine times out of ten I’ll walk between sites as I enjoy experiencing the sights, sounds and yes, even the smells of the City.

Lots of nooks and crannies to discover as well as the brilliant Thames Path.

In regards to your Bloomsbury to the Tower itinerary please note that Tower opening time.
https://www.hrp.org.uk/tower-of-london/visit/opening-and-closing-times/#gs.qd9lpm

You could easily arrive early at Tower Hill Station and stroll over to the adjacent Tower Memorial park. Grab a bench and send the 20 somethings over to stand in line for tickets. Once they were purchased you’d get a text from them. You’d cross the road at the light, walk across the moat and onto the Tower Grounds. If any in the party enjoy snapping iphone pictures, great view of Tower Bridge from outside the Tower of London. Inside the Tower grounds there’s a view of The Gherkin. So a very old and iconic piece of London and a POV of London’s modern architecture in one frame.

From the Bloomsbury neighborhood and depending on which tube station is closest to where you are staying its a 25-30 minute ride to the Tower Station which directly across the road from the Tower. Might have to change trains as well…but once you get the hang of The London Underground it’s a great way to negotiate London.

Why not just play it by ear? See how people in the group feel that day. Know that transfer stations, where numerous lines converge, can have long walks.

I’ve used both black cabs and even Uber in London to good effect. When my back starts giving out I either flag a cab or get an Uber. I like to conserve my energy for the actual sightseeing and not try to walk between sites or make long walks between tube station transfers. You need to help the 60 year old not push themselves to keep up w the energy level of the 20 year old. Rick’s point in the book is that using a cab or Uber is can be cheaper (depending on length of trip) and easier with four people than schlepping down to the underground or figuring out bus routes.

I’ve used both black cabs and even Uber in London to good effect. When
my back starts giving out I either flag a cab or get an Uber. I like
to conserve my energy for the actual sightseeing and not try to walk
between sites or make long walks between tube station transfers. You
need to help the 60 year old not push themselves to keep up w the
energy level of the 20 year old.

That's been my experience too, although I haven't used Uber in London, the black cab rides were rare, and in my case it's a hip. A few times on my last visit to London, I pushed too hard, and made long long walks inside Tube stations that are ugly memories. I prefer long walks in, say, Hyde Park, to long underground trudges to and from Tube platforms, and try to judge my energy and comfort levels accordingly.

I chose to make some trips by bus instead of Tube, because it was easier to judge the actual walking distances involved beforehand, and I wasn't pressed for time. The plus side of bus rides: I got to see the streets as we drove through them. The downside of course: all the time spent sitting stopped in traffic.