Depending on when it is, at least the British army would have enough veterans of the Boer War (e.g. a young, competent Sir John French, numerous skilled marksmen who know how to use camoflage, Baden Powell...) to have an impact. Still wouldn't trust them to perform miracles, due to the general old fashionedness of the pre Haldane Reforms British Army (no General Staff), and their general lack of numbers and experience compared to the Russian Empire. Both sides fumble around, throw a few blows, spend more than a few million pounds, and stop fighting. Indian independence, depending on how long it lasts, may gain ground-but not that much unless Britain is really stretched. (The Indian National Congress at this point still didn't actually want it, after all.)
Funny-upon entry to WWI, the only two European armies involved to have any modern combat experience (as opposed to the Ottomans and Italians, who turned up later) were the Russians and the British. Both didn't do well in their pre WWI wars. And both often (especially the Russians, although this does turn up in the anti Haig threads quite a lot) get criticised as being a bunch of archaic Victorian incompetents. Which doesn't completely work out when you look at their actual 1914 armies (with their relatively plain uniforms, in the Russian case I heard they on paper had the most machine guns/batallion of any great power as well as some of the best aircraft, and the British had actual fire and movement tactics for the infantry), but this is getting off track.